1
Sarah Cremin
From: Elaine ORourke <[email protected]>Sent: 29 January 2019 16:05To: Patrick FanninCc: Public Accounts CommitteeSubject: NPHDB Documentation for Public Accounts Committee Attachments: List of Independent and Internal Corporate Reports for PAC (ID 46124).pdf; MEP
DSSR Review Report.docx (ID 45754).pdf; NPHDB 2017 Financial Statements (ID 33634).pdf; NPHDB Briefing Paper Presentation for PAC Jan '19.pdf; NPHDB Financial Position Update.pdf; Role of GCCC NDFA and OGP on NCH Project (ID 46058).pdf
Categories: Red Category
Ref: PAC32‐I‐1291 Dear Pat We attach the briefing paper presentation and requested documentation as listed below as requested by the Public Accounts Committee.
1. Briefing Paper – Presentation Attached (file name: NPHDB Briefing Paper Presentation for PAC Jan’19)
2. 2017 Financial Statements – Document Attached (file name: NPHDB 2017 Financial Statements) 3. An update on the financial position since the last set of accounts - Document Attached (file name:
NPHDB Financial Position Update) 4. A note on the current position on the National Paediatric Hospital project – Included within NPHDB
Briefing Paper Presentation, Slide No. 15 5. A note on the basis used to establish the costs of the project and the comparisons used - Included
within NPHDB Briefing Paper Presentation, Slide No. 10 6. A list of any independent or internal corporate reports relating to reviews, examinations or audits in
relation to corporate governance or internal financial controls. The list should include the subject of the report, the report author(s) and the date of sign-off, completion or publication. – Document attached (file name: List of Independent and Internal Corporate Reports for PAC)
7. Information on the role of the National Development Finance Agency and the Office of Government Procurement in the procurement arrangements for the National Paediatric Hospital. – Document attached (file name: Role of GCC, NDFA and OGP on NCH Project)
8. Copy of the review conducted by DSSR in 2018 examining the mechanical and electrical systems for the National Paediatric Hospital. – Document attached (file name: MEP DSSR Review Report)
People attending on behalf of NPHDB: Names of those appearing before the committee 1. Tom Costello, Chairman, NPHDB 2. John Pollock, Project Director, NPHDB 3. Dr Emma Curtis, Medical Director, NPHDB 4. Jim Farragher, Finance Officer, NPHDB Gallery 5. Rhonda Evans, NPHDB 6. Angie Kinane, NPHDB Thanks
2
Elaine O’Rourke
______________________________ Elaine O’Rourke Senior Executive Administration National Paediatric Hospital Development Board NCH Office, Block A, Herberton, St. James’s Walk, Rialto, Dublin 8 E‐mail: [email protected] | Landline: 00 353 1 556 4538
This e-mail is from NPH. The e-mail and any files transmitted with it are confidential and privileged and intended solely for the use of the individual or entity to whom they are addressed. Any unauthorised direct or indirect dissemination; distribution or copying of this message and any attachments is strictly prohibited. If you have received the e-mail in error please notify [email protected] +353 (1) 556 4538 and delete the e-mail from your system. Consider the environment - only print this email if necessary
This e-mail is from NPH. The e-mail and any files transmitted with it are confidential and privileged and intended solely for the use of the individual or entity to whom they are addressed. Any unauthorised direct or indirect dissemination; distribution or copying of this message and any attachments is strictly prohibited. If you have received the e-mail in error please notify [email protected] and delete the e-mail from your system. The NPHDB operates in accordance with the General Data Protection Regulation (GDPR). When you receive an email from us it's because we believe that you have a legitimate interest in receiving it. Please refer to our Privacy Statement on our website at newchildrenshospital.ie for more information on how we safeguard your personal data.
NPHDB Capital Budget Update Public Accounts Committee
31st January 2019
Tom Costello, NPHDB ChairJohn Pollock, NPHDB Project DirectorDr Emma Curtis, NPHDB Medical DirectorJim Farragher, NPHDB Finance Officer
Largest Healthcare Project in the History of the State
One Children’s Hospital & 2 OP & UCCOne of the Largest and most complex public sector projects ever.
Slide No. 1
Start Construction
Enabling Works
Shortlisting Contractors &
Tender Enabling
Oral Hearing
Government Approval 26th April appoint Main & Satellites
Contactors
AU
G 2
015
DE
C 2
015
AP
RIL
201
7
MA
RC
H 2
016
JUL
Y 2
016
new children’s hospital will
be completed in 2022
NCH Overall Ten - Year Programme ….
Design Commenced
AU
G 2
014
2019
2022
Planning Submitted
2023
AU
G 2
013
NPH Board Appointed
End of Defects Liability
ABP Decision Date
AP
RIL
201
6
2020
Paediatric OPD & Urgent Care Centre
at Tallaght built
Paediatric OPD & Urgent Care Centre
at Connolly built
Slide No. 2
New Children’s Hospital …. it’s a complex unique project
• New children’s hospital at the St James’s Hospital campus (c. 158,000m2)
▪ Over 6,000 heavily serviced rooms
▪ State of the art ‘Digital Hospital’ with ICT integration & resilience with duplication/backup of ict systems
▪ 473 beds (380 In-patient & 93 day care, single bed rooms)
▪ Play areas, external gardens and courtyards (4 acres) for patients & staff
▪ Central concourse for ease of wayfinding (site length of Grafton Street)
▪ Third Level Education Centre & Hospital School
▪ 1,000 space basement car park, Retail facilities
▪ SJH Services decanted, 20,000sqm buildings demolished,12 acre site cleared
▪ Sustainability embedded in design, A3 Energy Rating BREEAM Excellent rating
▪ Outpatient & Urgent Care Centres at Tallaght & Connolly hospital (c. 9,000m2)
Background
Slide No. 3
Background - Wider benefits
- Improved facilities and investment at St James’s Hospital, decant of services (pharmacy, laboratories, infrastructure etc)
- Improved facilities at Tallaght Hospital, decant and creche
- The project’s scale and national importance a catalyst for regeneration of surrounding neighbourhoods and businesses
- Dublin 8 Urban Regeneration Committee established with IDA, DCC
- Local Community Benefits programme, social clauses in construction contract with 4 pillars;
1. Local Employment & Training Opportunities2. Local Economic Development3. Raise Aspirations through Education 4. Community Health & Wellbeing
Slide No. 4
Background …. 2 - Stage Procurement
- The construction tender Procurement Strategy adopted in 2014 by the NPHDB, accepted by Government Construction Contracts Committee (GCCC) and issued for Tender in 2016 was a 2-stage approach:
- Stage 1 A full tender for the basement substructure Phase A works** on the basis of a detail design, with a full bill of quantities* and tendering the main above ground Phase B works*** on a Preliminary 1st stage design with an approximate and remeasurablebill of quantities reflecting the Preliminary 1st stage design.
- Contract Awarded August 2017
- Stage 2 : While the basement Phase A works are under construction, complete the 2nd
stage Detail design for the above ground Phase B works with a full bill of quantities priced at the 1st stage Preliminary design tendered rates.
- Phase B works instructed Dec 2018
*Bill of quantities: itemisation of what is included in the construction works with item quantities and prices per item
**Phase A works are the below ground works consisting of basement, drainage, foundation, piling
***Phase B works are the 7-storey above ground works consisting of structural frame, façade incl windows, roof and all Mechanical & Electrical works
Slide No. 5
➢ Early commencement on-site, 2 years ahead of traditional procurement
➢ Cost savings, in an inflationary construction market procure at 2016 v 2018 market rates
➢ Engagement from Irish & International contractors to increase market competition
➢ Opportunity for contractors to influence/interrogate design and take responsibility for completeness
➢ Cost certainty and design certainty prior to instruction of Phase B
➢ De-risk project, claims are addressed up front, prior to Phase B instruction, rather than through 4 years of claims to 2022
➢ Single point accountability for site management of Phases A & B
Examples: St Vincent’s Private Hospital, Ulster Hospital Phase 1/2, ESB Headquarters, NDFA Boland’s Mills, UK NHS Procure 22 Strategy, Great Ormond Street Hospital Zayed Centre,
2- Stage Construction Procurement Benefits
Slide No. 6
1. Contract Signing (Phase A&B) Aug ’17(BAM lowest tender by €130m)
2. Instruct & Start Phase A works Oct ’17(with option not to instruct Phase B)
3. Phase A on Site (Below ground works)(complete early 2019)
4. Detail Design & Cost Phase B(completed Nov ’18)
5.
6,
Phase B above ground works approvals Dec ’18
Phase B above ground works on Site, complete 2022to 2022
Instruct Phase B Works
One Contract / Two Phases
Detail design, price Phase B
Construct Phase A Basement
Issue Tenders June ‘16
Slide No. 7
Background
Project Status Today:
- SJH Services decanted, buildings demolished & 12 acre site cleared
- BAM awarded contract/Jones Group and Mercury Engineering awarded M&E contracts Aug 2017 (BAM tender €130m lower than 2nd ranked tender)
- Phase A below ground works commenced Oct 2017, completion early 2019 on budget
- Connolly satellite completion April 2019,
- Tallaght decant & creche completed November ’18, satellite mid 2020
- Phase B above ground works, approved December ’18 and instructed to BAM
- Overall capital Project Costs have increased to €1.433bn
- Due to increased scope in Phase B construction works the overall construction programme (Phases A & B) extended from 48months to 57months. Main nch construction completion Q3 2022
- Construction tender inflation from 2013 to 2018 has continued to rise
Slide No. 8
HSE Capital Funding
Core construction hospital and satellites centres €650mHSE capital funding of €650m approved by Government in 2013 for the core hospital
(nch at St James Campus and 2 OPD Urgent Care Centres at Connolly & Tallaght).
NPHDB Cost Estimate 2014*
Element Budget Comment
Core construction, hospital including 2 satellite centres €650mAs per 2013 approved HSE capital funding for core construction elements. Based on 3% per annum year on year construction inflation, completion 2019
Non-core construction, 3rd level education, academic centre, research etc
€140m
Funding by Department of Education and Skills/ Higher Education Authority, philanthropy etc
Non-core construction, hospital school Funding by Department of Education and Skills
Non-core construction, commercial area (car park and retail) Funding by private/commercial sources
Non-core construction, euipment Funding by HSE revenue funding (Managed Equipment Services) or HSE capital funding
NPH Cost Estimate May ‘14 €790m* Overall approved, June ‘14, budget for core and non core project
Additional scope - campus shared services, avoids service duplication, added in early 2015
€10mFor SJH & Maternity ( e.g. energy centre, clinical decontamination, facilities management, HSE capital funding approved in mid 2015).
Updated NPH Cost Estimate mid ‘15 €800m Overall approved mid 2015
NPHDB Budget Estimates 2014 €800m
*The 2014 NPHDB Budget of €790m, was based on advice from AECOM (Quantity Surveyors for Mater children’s hospital proposal). The estimate included construction cost per sq.m. of €2500. The inflation allowance of 3% p.a. up to 2019 compounded to 15% giving an overall cost per sq. m. of €2875.
Slide No. 10
Current Capital Cost Update
Core & non core elements €800m As per Cost Estimate ’14/’15
ElementIncrease Cumulative
Cost Comment
Higher Construction Tender Inflation
€143m
Original May ’14 Budget assumed 3%/annum tender inflation,
last updated Nov ’16 to reflect current market tender inflation up to 9%/annum for large scale, complex, Dublin projects
Extended overall project timeline Hospital scheduled to be completed in 2021
Construction tender receipts €40mConstruction tenders approved Jan’17, higher than budget estimates
Total €983m*Included in Definitive Business Case - Feb ’17
Based on targeted Value Engineering savings of €66m
NPHDB Budget Estimates Feb ’17 €983m (post tender)
Of the €983m total cost;• NPHDB costs only, does not include Children’s Health Ireland costs for ICT, EHR, Integration costs or family accommodation unit cost
• In April 2017 Government approved the investment required to enable the National Paediatric Hospital Development Board to award the construction contracts
Slide No. 11
Statutory Issues, Sprinklers
Cost Drivers Stage 1, June ‘16 to Stage 2, Dec ‘18
Tender Price €637m v
Target €570m
BOQ + Pricing Matrix
Initial Clinical User Requirements
Stage 1 Prelim Design
Detail Design Targeted Savings VE, extended programme, preliminaries, contractor claims, omissions
Final Clinical User Requirements
Instruct Phase BDec ’18
€890m
Statutory IssuesActual Quantities
Omissions in Design
STAGE 1 procurement June ’16 (120 rooms) STAGE 2 procurement (full 6,000 rooms Oct ‘17 to Dec ’18)
Slide No. 13
1User
Engagement
2Detail* Design
3Statutory
4Omissions
in Design/BOQ
5Loss of
Alternatives (VE)
6Extended
Programme,Preliminaries
7Claims Total
(excl vat)
€21m €94m €27m €20m €46m €90m €22m €320m
Summary Construction Cost Drivers*
* Refer to Appendix 1 Cost Drivers for more detail
Slide No. 14
Capital Cost Update
Overall Project Costs €0.983bn
In April 2017 Government approved the investment required to enable the National Paediatric Hospital Development Board to award the construction contracts
ElementIncrease Cumulative
Cost Comment
Construction Cost Increases inclextended 9month project timeline
€320mAs per items 1-7 Summary Construction Cost Driver Update. Total Construction Cost €890m
Other Construction works (Satellites, Enabling, Aspergillus, Decant)
€13mSatellites M&E financial collapse of 2 contractors, reverted to 2nd
ranked, unknown services, increased scope, contractor claims
Project costs; staff, offices, project insurances, planning contrib, design team, construction management, site supervision architects, engineers
€36mExtended timelines main nch and satellites. Enlarged site supervision team during construction and extension to 2022
Equipping of 2-Satellites and Main nchhospital
€16mDetailed schedules for 250,000 pieces of equipment completed. Imaging equipment procured for Connolly & Tallaght
Risk €11m Increased contingency provision
VAT €50mTotal Vat provision for project is €180m, circular tax returns
to exchequer
Total €1.433bnApproval from Government Dec ‘18 to instruct Phase B
Construction Contract
Overall Project Capital Cost Post 2-Stage Process Dec ’18 €1.433b
Slide No. 15
▪ Change in scope eg changes in clinical standards/practise
▪ Excess national tender construction inflation above 4%, post July 2019
▪ Changes in legislation eg Vat, prsi, labour rates, building regulations etc
▪ Changes with emerging medical technologies and compliance with regulatory or best practice guidelines at completion in 2022
▪ 53 Bed Family Accommodation Unit for families
▪ Children’s Health Ireland (CHI) Costs; ICT Infrastructure, EHR, Integration,
CRIC
Exclusions
Not part of NPHDB Capital Project
Slide No. 16
Under the Contract the Phase B above ground works did not have to be instructed to BAM. Prior to NPH recommending instructing Phase B other options were examined:
Option 1: Don’t award Phase B to BAM and retender project to the market
- A new public procurement process with further delay to project completion of 1.5 to 2 years
- Further Construction Cost increase of €305m incl vat, additional to €1.43bn
- Split contractual responsibility for Phases A and B
- Increased risk for project, claims, lack of market engagement, cost uncertainty etc
Option 2: Don’t award Phase B to BAM and tender for Management Contractor
- Non standard public procurement process with further delay to project completion of 1 to 1.5 years
- Further Construction Cost increases of €260m incl vat, additional to €1.43bn
- Split contractual responsibility/liability for Phases A and B
- Increased risk for project, claim opportunities, multiple small contractors, cost uncertainty etc
Due to further delay, further increased costs and increased project risk both of the above options were rejected and the NPHDB recommended to HSE, DoH the Phase B works are instructed to BAM
Alternative Options considered for Phase B
Slide No. 17
Two – Stage & Instruct Phase B, Dec ‘18 1. Two Stage Procurement Process delivered the following
a) Project delivery 2+ years earlier than traditional procurement
b) Rates secured at 2016 tendered rates with saving in costs as a result of
earlier delivery.
c) Detail Design rigorously challenged & interrogated by 3 contractors for
quantity measure and any gaps/omissions
2. Costs determined prior to instruction of Phase B.
a) Based on a detailed frozen design and a fully aligned 57 month
programme with 3 contractors.
b) Pre-empts traditional post contract award, cost/programme challenges
which result in increases in post contract out-turn costs.
3. Phase A nearing completion, the project substantially de-risked in relation to ground conditions
a) (contamination; soil disposal; archaeology; piling; rock anchors; adjoining owners) in parallel with the 2nd stage procurement process
Early Completion by 2 years
Costs, priced at 2016 rates
Project de-risked prior to Phase B
instruction
4. The Board is committed to ensure that the project is delivered on time and on budget and support the HSE external review of 2-stage process and implementation of recommendations
Slide No. 18
Description of Cost Driver Categories
1. Final Clinical User Engagement +€21m
• 2016 Tender, User Engagement with clinicians ( nurses, doctors) had not concluded. (120 typical rooms out of 6000)
• User Engagement process continued after 2016 tender documents for full 6000 rooms and laboratories
• 2016 provisional sum tender allowance for Group 1 Fittings, eg sanitary fittings, theatre lights/pendants etc. Tenders received in 2018 were higher than provisional sums.
• Additional data/ sockets/ medical gas outlets, ICT data points, etc. incorporated into final 2018 design, priced at 2016 tender rates.
2. Detail Design +€94m
• Provisional estimated quantities priced in 2016 Stage 1 preliminary design and applied to final Stage 2 detail design quantities. Overall quantities increased when scaled up to detailed designed 6000 rooms
• Laboratory and kitchen design completed after tender. Increase in electrical/mechanical systems, ICT- Digital Hospital, drainage, pipes/ fittings, air vents, facades, glazing and partition systems, priced at 2016 tender rates.
• Contractors interrogation of design to assess, buildability risks, gaps, omissions, challenges to method of measurement. Disputes/claims resolved by independent expert, excluding these as a basis for future claims.
Slide No. 23
Description of Cost Driver Categories
3. Statutory Issues +€27m
• Two key events during the detailed design;
1. Conditions attached to the Fire Certificate affecting the detailed design, including An Bord PleanalaDecision in Nov ’17 relating to the inclusion of fire sprinklers throughout the building
2. Changes incorporated during the detailed design period to reflect the outcome of the Grenfell fire as advised by the Fire Engineers.
4. Omissions in the Stage 1 Design / BOQ +€20m
• Any omissions to the design or Stage 1 quantities are reflected under this category. Examples of these would include; containment electrical cable supports, fire stop detail, cladding to mechanical ducts/pipes
• Costs resolved by applying 2016 tender rates or if none available determined by independent expert
Slide No. 24
Description of Cost Driver Categories
5. Loss of targeted savings (VE) +€46m
• Schedule of 2016 targeted saving €66m
• Actual saving delivered in 2018 €20m, a reduction of €46m below the targeted saving
• Some saving proposals not viable, eg infection control requirements, impact on running cost, savings less than anticipated
6. Extended construction programme by 9months & increased preliminaries +€90m
• Extended Time Alignment of three contractors (main, mechanical, electrical) construction programme. Construction programme is 9 months longer than tendered in 2016, with a pro-rata increase (as tendered) for extended time (€45m)
• Increased Preliminaries (Fixed & Time) for increased scope/ construction labour on site for the next 4 years with additional cost; canteens, drying/ locker rooms, scaffolding, hoists turnstiles, storage areas, generators, tower cranes, mobile cranes, teleporters, etc. Increased management/supervision staff incl engineers, site agents, planners, surveyors etc consumables, fuel, water, power, phones, IT. These additional costs apply over the full 57month programme. (€45m)
-
7. Contractor Claims +€22m
• Claims submitted by 3 contractors, adjudicated and determined by the independent expert eg M&E systems clashes, mark-up on specialists etc
Slide No. 25
Draft Financial Statement Update for 2018 , subject to Internal NPHDB review and audit by the C&AG.
Excl. Irrecoverable Total Excl. Irrecoverable Total
VAT VAT (Estimate) Cost VAT VAT (Estimate) Cost
€ € € € € €
2,401,601 552,368 2,953,969 6,874,829 1,594,633 8,469,462
16,769,432 3,856,969 20,626,402 48,678,254 11,213,873 59,892,127
262,199 35,397 297,595 27,043,371 3,972,570 31,015,941
88,648,063 11,967,488 100,615,550 114,396,049 15,261,678 129,657,726
(v) Equipment 3,647 839 4,485 3,647 839 4,485
(vi) Admin Costs 4,162,937 431,835 4,594,772 30,055,187 2,209,613 32,264,799
112,247,878 16,844,897 129,092,774 227,051,336 34,253,206 261,304,542
Excl. Irrecoverable Total Excl. Irrecoverable Total
VAT VAT Cost VAT VAT Cost
€ € € € € €
1,333,222 306,641 1,639,863 4,473,228 1,042,265 5,515,493
9,066,778 2,085,359 11,152,137 31,908,822 7,356,904 39,265,726
11,629,898 1,677,960 13,307,858 26,781,172 3,937,173 30,718,345
25,747,986 3,294,189 29,042,176 25,747,986 3,294,189 29,042,176
(v) Equipment - -
(vi) Admin Costs 11,677,455 391,714 12,069,169 25,892,250 1,777,778 27,670,028
59,455,339 7,755,863 67,211,202 114,803,458 17,408,309 132,211,767
* BST / CMS is Business Services Team / Construction Management Team
(iii) Site
development and
clearance
(iv) Construction
Draft 2018 Financial Statements
National Paediatric Hospital Development Board
(iii) Site
development and
clearance
(iv) Construction
2017 Cumulative to 31 December 2017
(i) BST / CMS *
(ii) Design Team
Total costs incurred to 31 December 2018 amount to €261.3m with costs of €129.1m incurred in 2018. The table
below shows the total cost incurred by cost category. As outlined in the accounting policy, VAT incurred in relation to
expenditure incurred by the NPHDB is not recoverable. The table includes the amounts relating to irrecoverable VAT
for information purposes.
2018 Cumulative to 31 December 2018
(i) BST / CMS *
(ii) Design Team
Listing of independent and internal corporate reports relating to reviews, examinations or audits in relation to corporate governance or internal
financial controls – 2017 to 2018
Author Subject Sign-off / Completion Date
Internal Audit Services
Mazars Internal audit services to close out the review of the GMP Process
November 2018
Mazars Review of Business Continuity and Disaster Recovery
August 2018
Deloitte Contract Management Review April 2017
Deloitte Stakeholder Review February 2017
Independent Reports
DSSR DSSR MEP Review October 2018
Aecom Benchmarking review to support GMP Process December 2018
Linesight Inflation Overview in the Irish Construction Industry (Update of 2016 report) – part of Design Team Fees
October 2018
Office of the Comptroller & Auditor General
C&AG Audits 2016 and 2017 Complete
Eversheds Review of the Code of Governance Manual (part of Company Secretarial Support)
May 2018
Eversheds Corporate Governance Review including Protected Disclosures and Skills Review
July 2017
Internal Report
Internal Report Process to Guaranteed Maximum Price November 2018
1
ROLE OF GCCC IN THE NCH PROCUREMENT PROCESS
• GCCC was involved with the NPH Procurement Sub-committee that met on the 24 January 2014 to discuss the NCH procurement strategy and the principal of the 2-stage procurement process
o The NPH procurement sub-committee agreed the appropriateness of the procurement strategy and 2-stage process at a meeting on the 28 February 2014 and these would be developed by the design team when appointed (which was in August 2014)
• On 20 May 2014 the NPHDB informed the GCCC of changes that would be required to the PW-CF1 public works contract to accommodate the procurement strategy and 2-stage process
• On 20 May 2015 NCH design team presented to the GCCC the NCH procurement strategy and 2-stage process and associated objectives
• Prior to the issue of the NCH tender documentation meetings were held with GCCC on 29 February 2016, 21 March 2016 and 06 April 2016 to reaffirm the procurement strategy, the 2-stage process and amendments to the PW-CF1 public works contract
• The GCCC assisted the NPHDB by amending public works contract templates (ITT and Tender and Schedule) required as part of the NCH tender documentation
• The GCCC was kept informed on the procurement of satellites contract
ROLE OF OGP IN PROCUREMENT MATTERS
• The OGP has assisted the NPHDB with the procurement of the following:
o Tender for the provision of General Legal Services and Planning Legal Services
o Tender for the provision of Internal Auditor Services under the OGP Framework
o Tender for the provision of Accounting and Financial Services under the OGP Framework
• The OGP has also provided the NPHDB with general procurement advice in respect of Reserved Contracts including other procurement matters
ROLE OF NDFA IN THE NCH PROCUREMENT PROCESS
• The NDFA had no role in the procurement of the NCH or satellite construction contracts
• The NDFA was involved in pre-qualification of the NCH design team tender shortlist in Qtr 1 2014 undertaking the financial robustness of application submissions
PROJECT | NATIONAL PAEDIATRIC HOSPITAL, DUBLIN
MEP PEER REVIEW
DSSR Document Reference Version
M4826-DSSR-X-XX-RP-MEP-XXX01 02
NATIONAL PAEDIATRIC HOSPITAL, DUBLIN MEP PEER REVIEW
Status: Purpose: For Review Date: 23/10/2018
Tracker Page M:\Manchester\Engineering\Projects\M4826 - NCH Dublin\3 Design\Reports\MEP Review Report_02 - 21.1.19docx.Docx
This Version
Authored by:
name: Mike Singleton
role: Partner
signed:
date: 23/10/2018
Reviewed by:
name: Tony de Caux
role: Partner
signed:
date: 23/10/2018
Authorised for Issue by:
name: Tony de Caux
role: Partner
signed:
date: 23/10/2018
The signed original of this page is retained by the issuing team. Version History
Version Date Status and Purpose Changes Overview
01 17/09/2018 For Review
02 23/10/2018 Final Issue
NATIONAL PAEDIATRIC HOSPITAL, DUBLIN MEP PEER REVIEW
Status: Purpose: For Review Date: 23/10/2018
Contents Page M:\Manchester\Engineering\Projects\M4826 - NCH Dublin\3 Design\Reports\MEP
Review Report_02 - 21.1.19docx.Docx
Contents
1 EXECUTIVE SUMMARY ..................................................................................................................... 1
1.1 Methodology .......................................................................................................................... 1
1.2 Compliance ............................................................................................................................ 1
1.3 Design .................................................................................................................................... 2
1.4 Risk ......................................................................................................................................... 3
2 MECHANICAL SYSTEMS ................................................................................................................... 3
2.1 Ventilation Systems .............................................................................................................. 3
2.1.1 Overall Ventilation Strategy 3
2.1.2 Operating Theatres 6
2.1.3 Isolation Rooms 7
2.1.4 Laboratories 7
2.1.5 Imaging Rooms 7
2.1.6 Single Bed Wards 8
2.1.7 Consult/Exam Rooms 9
2.1.8 Humidification 9
2.1.9 Specialist Ventilation Review Meeting 10
2.2 Chilled Water and Cooling ................................................................................................. 11
2.3 LTHW Heating ...................................................................................................................... 12
2.3.1 Boilers and Ancillaries 12
2.3.2 Primary Fuel 13
2.3.3 Stand by Fuel 13
2.3.4 Distribution 13
2.4 Steam .................................................................................................................................... 14
2.4.1 System Configuration 14
2.4.2 Boiler and Generator sizing 15
2.4.3 Ancillary components 15
2.4.4 Condensate Recovery and disposal 16
2.4.5 Resilience and Maintenance 16
2.4.6 Contractor’s Design Proposals 17
2.5 Water and Drainage............................................................................................................. 17
2.5.1 Water Supplies 17
2.5.2 Storage Volume 17
2.5.3 Segregation of risks 18
2.5.4 Booster arrangements 19
2.5.5 Hot water generation 19
2.5.6 Hot water circulation 19
2.5.7 Legionella Management 19
2.5.8 Oculus Consultancy Report and NPHDB Response 20
2.5.9 Drainage Systems 20
2.5.10 Drainage Materials 21
2.6 Medical Gas installations ................................................................................................... 21
2.6.1 Oxygen 22
2.6.2 Nitrous Oxide 22
2.6.3 Entonox (Nitrous Oxide/Oxygen mix) 22
2.6.4 Medical Compressed Air 23
NATIONAL PAEDIATRIC HOSPITAL, DUBLIN MEP PEER REVIEW
Status: Purpose: For Review Date: 23/10/2018
Contents Page M:\Manchester\Engineering\Projects\M4826 - NCH Dublin\3 Design\Reports\MEP
Review Report_02 - 21.1.19docx.Docx
2.6.5 Surgical Compressed Air 23
2.6.6 Medical Vacuum 23
2.6.7 Laboratory Gases 23
2.7 Building Management System ........................................................................................... 23
2.7.1 Performance Documentation 24
2.7.2 Control Strategies 25
2.7.3 Contractor’s Proposals 25
2.7.4 Observations Related to Performance Specification 26
2.8 Equipment and Systems Specifications ........................................................................... 29
2.8.1 Equipment Schedules 29
2.8.2 Proposed Manufacturers 29
3 ELECTRICAL SYSTEMS .................................................................................................................. 29
3.1 Electrical Infrastructure and Resilience............................................................................ 29
3.1.1 Incoming Supplies 29
3.1.2 Stand by Generation 30
3.1.3 Sub Stations 30
3.1.4 UPS 31
3.1.5 IPS 31
3.1.6 MV Distribution 31
3.1.7 LV Distribution 32
3.2 Earthing and Bonding ......................................................................................................... 33
3.2.1 MV Earthing 33
3.2.2 LV Earthing 33
3.2.3 Generators 34
3.2.4 Patients and Medical Equipment 34
3.3 Fire ........................................................................................................................................ 34
3.3.1 Fire Strategy 34
3.3.2 Fire Detection and Alarms 35
3.3.3 Evacuation Strategy 35
3.3.4 Fire Alarm Cause & Effect 35
3.3.5 Smoke Damper Switching Strategy 35
3.3.6 Smoke Ventilation 36
3.3.7 Fire Rated Ductwork / Fan Systems 36
4 DEROGATIONS REGISTER ............................................................................................................. 36
5 OTHER MATTERS ............................................................................................................................ 39
5.1 Supporting Infrastructure between M&E Systems .......................................................... 39
5.1.1 Mechanical Plant and BMS Power Supplies 39
5.1.2 Cooling of Electrical Equipment Rooms 39
5.1.3 Load Restoration / Generator Load Shedding 40
5.1.4 Plant Replacement Strategy 40
5.2 Spatial Coordination Capacity in Primary distribution ................................................... 41
5.3 Robustness of Performance requirements for Contractor Designed Elements .......... 43
5.4 Future Flexibility .................................................................................................................. 43
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1 EXECUTIVE SUMMARY
1.1 Methodology
The approach taken to the reviewing the project has been to carry out a high level review of the Arup
stage 2C design drawings and other information provided by NPHDB for comment.
Services elements reviewed include;
• Ventilation layouts
• Heating systems
• Water services
• Medical gases
• Steam & condensate
• Electrical distribution
• Resilience and standby generation
• Incoming utility services
• BMS & automatic controls
• Plant areas & service risers including plant access and replacement strategies
The review focussed on the following issues;
• Compliance with design standards including UK, NHS guidance
• Design approach, i.e. quality of design, over engineering or inadequacies of design
• Value engineering
• Risk
In carrying out the design reviews comments were made against specific guidance and standards but
also in some instances recognising preferences and opinions based on our own design experience.
Where comments represent opinion or preference this has been made clear to avoid misleading.
In making some observations or recommendations we have recognised that even if the changes were
seen to be beneficial the design or construction process is too advanced to change at this stage.
1.2 Compliance
Based on information examined and meetings with the Arup team it is clear that the overall design
intent has been to comply with healthcare design guidance and develop rigorous design proposals
which address the requirements of the appropriate guidance and provide an appropriate level of
engineering systems to provide the service to each of the hospital departments.
There is no evidence that the design decisions have been generally cost driven with the aspirations
of the NPHDB for a “state of the art” facility providing the best environment for the care of the patients
and their families. Examination of the engineering solutions shows that the building services will reflect
the guidance applicable except where noted otherwise and agreed with the client.
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From the reviews carried out to date there are a number of instances where the MEP services design
does not fully comply with HBN or HTM requirements. Such derogations are noted in the derogation
schedules comments on which are noted in section 4 of this report. There are a number of derogation
worthy of review, particularly;
• Scope of humidification
• Fire rated cables from UPS
• Provision of catch trays to reheat batteries
• Cooling coils above ceilings
• Location of IPS units
• 12 hours water storage
Where we have identified any instances of noncompliance that Arup were unaware of these are
referenced in this report.
The most significant item is the fire rating of the isolation rooms and this is for the Fire Engineer to
comment on not Arup.
1.3 Design
The MEP design is generally very robust and reflects what is a complex building layout with services
requirements that are very exacting and well defined by HSE and other standards.
There are some elements where the detail design is by the Contractor and these elements do present
an increased risk with regard to maintaining the level of quality and robustness as the Contractor has
a different agenda to that of the Design Team. From discussions Arup are well aware of this risk and
are being forceful in their commenting and response to the Contractor’s proposals.
The MEP design has been through a Value Engineering review and it is now at a point where to
generate any further significant savings there would a reduction in the quality of the design and this
would need to acknowledged by changes to the agreed deliverables of the design or further
derogations agreed by all parties.
Value engineering decisions noted to date such as the omission of a spare electrical standby
generator or boiler for future use do not impact on the initial scope of provision and the appropriate
level of resilience, generally N+1, is maintained with the present proposals.
Particular observations raised in the report which merit further consideration include;
• Aspergillus prevention strategy
• Ward bedroom ventilation strategy
• Scope of humidification
• Generator loading strategy and reinstatement of power on start up
• Load shedding in caser of generator failure
• Spatial coordination challenges
• Development of electrical distribution protection and grading studies
• Development of fire cause and effect
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• LV electrical distribution comments
• Earthing strategy
1.4 Risk
Whilst the design proposals are generally robust and comply with the required standards and guidance
the are a number of areas where some risk remains. These issues are known to the design and
construction teams and are being addressed as the project develops into the installation stage.
Risk areas include;
• Plant access and replacement strategy – this is being reviewed by the installation contractors to
ensure that actual plant selections can be installed, maintained and replaced.
• Provision of a resilient oxygen distribution strategy – duplicate oxygen systems are proposed
including a link to the St. James Hospital however this critical service could benefit from further
resilience by retaining/relocating the temporary VIE installation.
• Specialist contractor design elements – whilst the evidence reviewed shows that the Arup design
intent is robust and that contractor design proposals will be challenged where not in accordance
with the performance requirements there remains a risk, particularly if cost pressures arise, that
the final designs proposals may not meet the initial aspirations.
• Spatial coordination – it is clear that this is a very heavily serviced building with ceiling voids and
service risers being very congested. Review of coordination shows that there are a number of risk
areas which will need careful consideration by the installers to achieve an accessible and
maintainable installation. This is being addressed but will require careful monitoring during
construction to ensure a satisfactory outcome. Space for future services to be added in many
areas is very limited.
2 MECHANICAL SYSTEMS
2.1 Ventilation Systems
2.1.1 Overall Ventilation Strategy
The building form and the requirements of the various spaces has resulted in a ventilation strategy for
a building that is predominantly mechanically ventilated with the exception of the upper level ward
accommodation that is naturally ventilated where possible.
There a number of points that have an impact on the design solution, cost or are an interpretation of
the applicable standards that needs to be accepted by all parties and these are:
i. Infection from Aspergillus has been identified as a risk to patients within the children’s hospital
as a result of the future construction of the Maternity Hospital adjacent to the New Children’s
Hospital.
This risk has resulted in the provision of additional filtration, to HEPA standards in ventilation
plant and additionally within the natural ventilation openings in ward bedrooms.
The provision of HEPA filters is a requirement of HSE regulations and whilst F9 filtration may
be considered adequate compliance with the standard is expected.
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It must be noted that the provision of additional filtration, particularly of HEPA standard, will add
substantial cost, including the increase in fan power to overcome the significant additional
resistance.
The provision of HEPA filtration is particularly problematic in areas of natural ventilation, such
as ward bedrooms, where it will become necessary to add a fan to the ventilation openings.
It is not known how this issue will be dealt with in other areas of natural ventilation but the risk
must be assessed and a strategy defined. This is yet to be confirmed.
It is not known when, or if it is certain, that the Maternity Building will be constructed so given
the costs involved it would be reasonable to review the approach and consider if the requirement
for HEPA filtration must be applied.
Guidance relating to the prevention of infection from Aspergillus spores in the UK has been
reviewed and whilst the risks are widely acknowledged, with a particular risk to immuno-
compromised hospital patients and especially those suffering from certain conditions such as
asthma, and with a particular risk from hospital demolition and construction sites, there is little
relevant guidance on the prevention of infection.
The guidance which does exist, published by the Health & Safety Executive relates to the control
of the spread of spores on the demolition or construction site and the protection of the operatives
on the site. Advice presented includes the usual dust prevention measures of wetting down of
dusty tasks and wearing of masks etc.
Further guidance relating to protection of occupants of adjacent buildings includes;
• Decanting of affected areas
• Closing windows
• Isolating ventilation systems
• The use of air purification units
As none of the above are practical or helpful in a large hospital the question is left largely
unanswered.
Where similar situations have arisen on existing sites preventative measures have been
considered and practical steps taken to control the risk including;
• Air sampling before and during construction works
• Air sampling within air distribution systems before and during construction works
• Checking filter seals to ensure no dust is bypassing filters
• Management the creation and spread of dust on the construction site
• The use of air purification units in limited affected areas
It is clear that the provision of HEPA filtration, particularly to areas which should be naturally
ventilated, is adding significantly to the cost and complexity of construction and operation of the
hospital.
If the future construction of the Maternity Hospital was not known at this time would the same
provisions be included?
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It is suggested that the guidance be reviewed to establish the need for such measures and the
risk if not included however it is accepted that having identified the risk the precautionary
measures become unavoidable.
It must also be recognised that HSE standards require provision for the protection against
aspergillus spores and the omission of HEPA filtration will only be possible with the agreement
of HSE and client teams.
ii. F7 filters are selected as pre-filters in line with HSE requirements with F9 main filters and
provision for installing HEPA filters in the east side air handling plant due to the aspergillus risk
from the Maternity Hospital construction.
This increased level of filtration will impact on initial capital costs and also on running costs due
to increased fan power.
It is noted that the filtration strategy has been agreed and would require a client instruction to
change involving redesign and potential delays.
iii. Ventilation plant is located at level 3 above the podium block and at roof level above the ward
block.
Ventilation plant serving the fingers is located at basement level which creates problems with
air intake and discharge. It has been confirmed that this is necessary to comply with planning
requirements limiting the height of these blocks due to the proximity to residential areas.
The air intakes have been arranged in courtyards via feature air intakes and below ground ducts
which will avoid the risk of drawing in vehicle exhaust fumes etc. Air discharge is arranged via
the car park.
Whilst adding to the cost of the installation it is necessary to comply with planning and avoids
the risks associated with low level ventilation plant.
Ventilation plant at level 3 is enclosed on 3 sides leaving only a single façade for fresh air intake
and exhaust. Guidance suggests that intake and discharge should ideally be on opposite sides
but if on the same side separation of at least 4m should be achieved with exhaust at a higher
level than intake. BREEAM requires separation of 10m which has been achieved in the design
proposals.
Installation should be monitored to ensure this separation is not compromised during
construction.
iv. It is noted that frost coils have been omitted from air handling units, which is contrary to HTM
03. This omission could, under extreme conditions, result in freezing of the intake filter, however
this is considered an unlikely eventuality particularly with the typical climatic conditions in Dublin.
The normal panel pre-filters have been replaced with bag filters as these are more robust in
construction.
The decision to omit frost coils was taken during the initial value engineering exercise and is
noted in the schedule of derogations.
It should also be noted that the omission of frost coils significantly improves heat recovery and
has been agreed and would require a client instruction to change involving redesign and
potential delays. The reintroduction of frost coils would also impact on spatial coordination in
plantrooms due to the additional length of air handling plant and the pipework to the coils.
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The ventilation system design includes numerous zone or room reheat batteries distributed with
the departmental ceiling voids. This approach provides flexible and room/zone specific control
of temperature allowing the air supply temperature to adjust to satisfy the heating and cooling
requirements of each area, but is however expensive. The strategy may offer some
opportunities to reduce costs but some compromise in control would inevitably result. It is also
noted that the strategy has been agreed and would require a client instruction to change
involving redesign and potential delays.
v. The stage 2b refers to draft HSE guidance regarding air handling plant requiring F7 pre filters
and F9 final filters.
It is also noted that the provision of F7 filters on the extract has not been adopted.
It is not stated when this guidance comes into force or if the guidance is expected to be applied
at this stage.
vi. It is noted that the ductwork installation to specialist areas, eg labs & audiology rooms, is shown
on the Arup drawings. As these areas are specified as specialist contractor design it is not clear
where the demarcation lies and there is the potential that the cost of services in such areas may
be double counted. Arup have confirmed that the demarcation of areas has been agreed and
costs are not double counted, and there is no evidence to suggest this is not correct.
2.1.2 Operating Theatres
i. Operating theatre ventilation is conventional and follows the guidance in HTM 03. Low level
extract ventilation is included as required and whilst exact location can be subject to
interpretation the proposals follow the guidance and are considered compliant.
ii. Air transfer from the theatre to anaesthetic room is at low level but from anaesthetic to corridor
at high level above the door which does not follow the spirit of maintaining air flow from high
level to low level however there is little option for an alternative solution.
The required low level extract has been included in 2 locations adjacent to the patient head,
creating the necessary direction of air flow to low level past the patient and anaesthetist.
Arup have recognised the risk and will consider CFD modelling to confirm air flow paths.
iii. It is noted that theatres are in some cases surrounded by fire walls which creates difficulties in
achieving the necessary air flows between theatre and corridors, requiring smoke operated fire
dampers installed with the pressure stabilisers.
The fire dampers have been included to give a compliant installation but the fire strategy should
be reviewed, particularly in light of the addition of sprinklers to avoid the inclusion of fire walls
around theatres.
The Fire Strategy should be confirmed by the Fire Engineers with respect to Theatre areas.
iv. It is noted that the ventilation proposals have been reviewed by Malcolm Thomas and no
concerns have been identified with respect to theatre ventilation although particular reference
to the air flow in anaesthetic rooms is noted and this is an area he will focus on during the
validation of the hospital ventilation.
v. The client brief specifies that “operating theatres will be designed in such a way as to be
independent with the emphasis on minimum theatre down time in relation to dealing with
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infectious cases, maintenance and upgrades” This rules out the potential for combining 2
theatres on a single air handling plant.
2.1.3 Isolation Rooms
i. Isolation rooms have been included with designs based on HBN 04-01 Supplement 1.
ii. It is noted that it has been agreed to ventilate 2 isolation rooms from a single plant as is
acceptable in HBN 04 as a compromise in high rise buildings. Whilst this strategy has been
adopted the proposal is to combine only 2 rooms together so is considered reasonable.
iii. The ventilation strategy generally follows the guidance in HBN 04 S1 and is considered to be
compliant.
iv. The fire strategy relation to isolation rooms is not compliant with HBN 04 S1 however the
ventilation design is consistent with the fire strategy as drawn.
It should be noted that HBN 04 2005 applies to isolation rooms in an acute setting, and requires
each isolation room to be considered as a separate fire compartment. This document has been
partially superceded by the 2013 issue but not in all aspects.
The Fire Strategy should be confirmed by the Fire Engineers with respect to isolation rooms.
2.1.4 Laboratories
A review of the ventilation strategy for the laboratory areas shows a design that is consistent with the
requirements to segregate both the supply and extract systems and to achieve the various levels of
containment.
The routing of all extract ductwork to discharge at Level 7 with high velocity discharges on all fume
cupboard extracts is compliant and in line with good engineering practice.
2.1.5 Imaging Rooms
i. Imaging areas are provided with mechanical ventilation and cooling with local reheat to rooms
where there is a risk of sub-cooling.
As this applies to many rooms the result is a large number of re-heat batteries in the ceiling void
of the departmental areas.
Whilst this is a compliant design it will also generate significant costs. The strategy could be
simplified to reduce the number of reheat batteries however this would result in compromise to
control and flexibility and potentially result in some rooms out of tolerance.
It is noted that the strategy has been agreed and would require a client instruction to change
involving redesign and potential delays and would reduce the environmental control.
ii. Local cooling via fan coil units is also included to areas of high heat gain.
iii. It is noted that humidification is included to a number of areas including specific imaging
systems.
Whilst it is commonplace to omit humidification on grounds of cost and maintenance humidity
control in imaging areas can be critical and should not be compromised.
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2.1.6 Single Bed Wards
i. Single bed ward bedrooms on levels 5 & 6 are proposed to utilise natural ventilation. This
approach is promoted by HBN 04 and is seen as an energy efficient solution which provides the
patient with control of their environment and access to fresh outdoor air. Whilst this is
undoubtably correct there are a number of concerns which must be recognised;
• Summer temperature control will not be as effective as mechanical ventilation with cooling.
• The cooling effect of ventilation by ambient air will always be limited in hot weather resulting
in internal temperatures which may be within the specified limits but some may consider
excessive.
• Outdoor air may contain pollutants, particularly where rooms are adjacent to traffic routes.
• Noise control is not possible without closing windows which eliminates the possibility of
ventilation.
• Control of opening windows is crude and the introduction of fresh air in winter may well
result in cold draughts and discomfort. The success is also reliant on patients or staff
reacting to changing conditions.
ii. The Arup design proposals have attempted to overcome the risks associated with natural
ventilation by including a number of complimentary elements including;
• Louvred ventilator at low level below the window/couch,
• A high level louvered ventilator above the window,
• A full height louvred panel adjacent to the window,
• Extract air via the en-suite wc/shower
iii. Additional optional elements considered include;
• Automatic control of the low and high level ventilators.
• The inclusion of filters, heating coil and cooling coil to the low level air intake.
• The inclusion of HEPA filter to satisfy concerns regarding Aspergillus contamination which
will then require the provision of a fan to overcome the resistance of the filter.
iv. The proposals have been modelled to take account of future trends to warmer summer
temperatures hence the area of ventilation openings included.
v. The resulting installation will offer a comprehensive solution to ward ventilation, however it is
considered that it will be an expensive installation, will require maintenance within the patient
room (particularly if HEPA filters and fans are included), and may prove confusing to occupants.
Arup have considered the control methodology and have evolved a combination of automatic
control of the low level vent with heating/cooling coil combined with manual control of natural
vent by the occupants. Whilst this remains a complex system operation by the users should not
prove too difficult to understand. The operation is to be reviewed in the mock up room to confirm
client satisfaction with the proposals.
vi. It is considered that the design concepts are sound the practical operation and maintenance
impacts require further refinement. The provision of HEPA filters and fans should be seriously
reconsidered although this must be subject to the risk from Aspergillus.
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vii. It is clear that the bedroom ventilation strategy could be simplified based on a more conventional
opening window arrangement but this would result in compromised performance, particularly if
the trend of future warming continues as predicted.
viii. An alternative may be to reconsider mechanical ventilation with cooling although this would be
a fundamental change of strategy and will have significant impact on plant areas.
Such a change of strategy has been considered but at this stage the change to conventional
mechanical ventilation would prove impractical and reverting to natural ventilation only via
opening windows would not achieve the required performance.
It is likely that whilst other options are possible the scheme is at such an advanced stage that a
fundamental change of strategy cannot now be achieved.
2.1.7 Consult/Exam Rooms
Outpatient consult/exam rooms are not provided with mechanical ventilation however the natural
ventilation strategy is not clear. The ward bedroom solution is not included to these rooms and it
appears to be a conventional opening window. The approach should be confirmed and the possible
conflict with patient privacy should be considered.
It has been suggested that the acoustic specialist reviews the arrangement although noise nuisance
is unlikely to be an issue as most consulting rooms do not face on to noisy areas. A greater risk is to
privacy if areas outside the rooms are accessible to public or staff and this should be confirmed with
the client.
2.1.8 Humidification
i. It is noted that humidifiers have been included on air handling plant serving critical areas.
ii. Humidification is proposed by the use of local electric humidifiers and whilst this is a practical
solution the use of a central steam system, possibly linked to the CSSD Primary steam
generators, may be more economic although initial capital costs may be higher. The FM team
may have a preference in this regard. (They would no doubt prefer to omit all humidifiers but
this is not possible).
Arup have confirmed that the use of local electric humidifiers has been discussed and agreed
and as this is not a significant risk or the benefit of change significant the present strategy will
remain.
iii. It is noted within the stage 2b Mechanical and electrical report that draft HSE guidance requires
the provision of humidification to maintain a minimum of 30% RH, it is not clear if this applies to
all mechanical ventilation systems or specific systems only. It is stated that this has not been
included in the project with humidification to limited areas only. The scope of provision should
be reviewed with the client team to ensure that adequate provision is included, particularly to
imaging, pharmacy and critical care areas.
Arup have confirmed that the derogation with regard to the provision of humidification has
previously been agreed and that an instruction will be required from NPHDB to change the
design.
It is noted this is urgent and has the potential to impact on ongoing coordination as the first
batch of air handling units is being ordered.
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It must be recognised however that the derogation refers to the air handling systems where
humidification is being included and does not address those systems where humidification may
be expected but not included. It would be preferable to identify all systems where humidification
may be expected and explain the current provision.
It may also be beneficial in some instances where humidification is excluded to include the
spare section in the air handling unit as noted in HTM 03. This may well cause coordination
difficulties in plantrooms but should be clearly defined and agreed with the client team.
2.1.9 Specialist Ventilation Review Meeting
The ventilation design proposals were reviewed jointly with NPHDB/CHG, Arup and Malcolm
Thomas/Sigrid Volkmann and others at a meeting on 25/01/2018 and the following points should be
noted;
i. The contractor has selected Wegner air handling units and whilst the manufacturer is not well
known to the design team the units have been reviewed by both Arup engineers and
CHG/Malcolm Thomas and the units were accepted subject to reliance “on the professional
judgement of the design team and their adherence to the specifications” This may leave the
question of acceptance open if there are any concerns raised retrospectively.
ii. External air handling units are noted and additional weather protection was requested by
extending the AHU roof over the access area or adding additional shelter.
Arup have confirmed that plant enclosures were considered but could not be accommodated
due to cost constraints. It is accepted that whilst not ideal this is a risk known to the client and
can be managed in operation.
iii. The omission of fog coils was discussed and refers to a “misunderstanding of the purpose of
fog coils” CHG requested that fog coils be reinstated unless it can be clearly demonstrated that
filters will not get damp or wet. It is clear that fog coils have been omitted so documentation of
acceptance should be retained.
Arup have confirmed that the derogation to omit fog coils has previously been agreed and an
instruction would be required from NPHDB to change the design.
It is noted this is urgent as reintroduction of fog coils will impact on ongoing coordination within
plantrooms and the first batch of air handling units is being ordered.
Whilst the agreement is less certain than would be desirable it is an accepted strategy which
carries little risk and some benefits so it is not considered justifiable to change at this stage.
iv. It has been agreed that the interior of the air handling units will be powder coated as an
alternative to rounded corners. The units will need to be treated for coastal conditions as Arup
specification so coating will be required. The need for rounded corners is not specific but the
“inside of plant should be as smooth as possible” (HTM 03 cl. 4.14)
v. Further research and feedback is noted prior to the final selection of UCV canopies, particularly
with regard to screen-less canopies. It is understood that screenless canopies have been
selected as manufactured by Howarth. These canopies are well proven so the concerns are not
clear but is should be demonstrated that the selection is accepted by all parties.
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vi. It is noted that anaesthetic room air flow is to be agreed between Malcolm Thomas and Jack
Quinn (Arup) It is understood that this has been subsequently agreed but this must be
documented for record.
vii. Reference is included to linking theatre ventilation with lighting control. Whilst this has been
applied previously the anticipated benefits have not been realised as momentary access
switches on the ventilation when it may otherwise not be required. The method of operation
should be agreed with users and Estates staff.
viii. CHG noted that a number of reheat batteries have been located in areas that are not easily
accessible, e.g. in-patient bedrooms. CHG then suggested that clinical and operational risk for
each reheat is evaluated and opportunities sought to mitigate this risk. Inspection of the
drawings shows a significant number of reheat batteries in ceiling voids and whilst catch trays
are retained where reheat batteries are above patient areas that does not really satisfy this
concern. The risk evaluations should be shared and documentation retained for record.
Arup are of the opinion that this has been agreed and whilst this appears justified the reference
to risk assessments suggests that the decision could be subject to future challenge in some
instances. The arrangement shown on the drawings is considered reasonable given the spatial
constraints and any risk relates to only to documentation of risk assessments.
ix. CHG have reinforced their intent to carry out an independent validation of ventilation systems
at first fix stage and performance validation post commissioning. Whilst comment has been
made by Malcolm Thomas it is unlikely that he will be involved during the validation process
and a further set of observations and opinions may be offered. It would be reasonable for the
future validation team to comment on the design intent prior to installation.
2.2 Chilled Water and Cooling
i. The initial design proposals included a total of 7 chillers giving N+1 redundancy but the seventh
chiller was omitted during the initial value engineering exercise. This is considered to be a
reasonable decision as peak cooling loads occur only infrequently and then only for short
periods.
ii. The remaining 6 chillers rated at 100% of the diversified load is consistent with good practice.
iii. The application of diversity to cooling loads is limited when compared to other services but does
occur in practice.
iv. It must be noted that the cooling load does not include 20% spare capacity, but if the expansion
space is utilised additional chillers will be dedicated to this area.
v. The above strategy is considered practical and results in minimal risk as in extremis load
shedding can be employed to maintain essential services.
vi. Both space and connections are included for the installation of the seventh chiller if required.
vii. The normal summer design conditions for Dublin have been 24oC and 60% RH however in
recognition of future trends Manchester data at 28/20 has been used as the basis of design.
Equipment has been selected to operate at temperatures of up to 32oC. 35oC was initially
selected but reduced during value engineering.
viii. It is noted that single fan coil units only are included to the IT hub rooms. Whilst less critical than
main equipment rooms it is often a requirement to provide some measure of redundancy in
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these rooms either N+1 or duplicate unite at say 50% duty. The appropriate level of resilience
should be agreed with the client.
It is recognised that duplicate cooling units are included to main equipment rooms and electrical
rooms.
Arup have confirmed that the single cooling unit has been agreed during previous value
engineering reviews and has been accepted.
ix. Chilled water flow and return temperatures of 8/14oC have been selected for the design which
gives a good compromise between chiller efficiency and cooling coil performance. Care will
need to be taken in the design of specialist areas such as MRI technical rooms and computer
rooms to avoid dehumidification via local cooling units.
It is recognised that the Arup design includes air extraction from the technical room which will
draw air from surrounding areas which will mitigate the risk of low humidity but this will remain
a risk in operation depending on conditions within the building.
x. Chilled water connections are shown in the design to MRI scanners for future extension by the
specialist scanner installer. It is not specified how the connection should be achieved and will
require an intermediate heat exchanger to separate the general chilled water flow from the non-
ferrous system required by the MR scanner. This system will not automatically be included by
the scanner installer and should either be defined in the present design or included in the brief
to the scanner supplier. Space will be required to accommodate the chilled water interface which
should not ideally be included in the MR technical room.
It is understood that provision of heat exchanger and associated equipment will be included
within the specialist installation package. The interfaces between work packages will need
careful coordination to ensure the correct overall system operation but the design intent defines
the necessary requirements.
2.3 LTHW Heating
2.3.1 Boilers and Ancillaries
i. The primary heat source is an LTHW boiler installation consisting of 3 No. 5 MW boilers, giving
N + 1 capacity.
ii. Medium temperature hot water was considered but low temperature selected as the preference
in order to achieve greater heat generation efficiency.
iii. In order to minimise pipe sizing flow and return temperatures of 80/60oC are utilised.
iv. The 10 MW estimated load is considered low when compared the arithmetic maximum but in
practice will satisfy the real building winter demand, which from experience of similar sized
hospitals is likely to be less than 8 MW. It would be unwise however to introduce further
compromise on the maximum load.
v. The boilers at first sight appear large but have a turn down ratio of 6:1 giving a minimum load
of 800 kW which would equate to the likely minimum summer load.
vi. Flexibility and resilience may be improved by utilisation of a greater number of smaller boilers
but costs and space requirements would increase.
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vii. An additional heat source is provided by the CHP and Arup advise that the boilers are sized
assuming that the CHP is not available. A number of options have been considered for the
combination selection of boiler plant and CHP resulting in the selection of a 2,000 kW, thermal,
CHP set which is matched to the site load to run for 6,000 hours initially rising to 8,000 hours
with NCH expansion and the addition of the proposed Maternity development.
The specified size of CHP set, at 2000kW, is consistent with benchmarked CHP installations on
similar projects
2.3.2 Primary Fuel
i. The primary fuel for boiler plant is natural gas as would be expected for a development of this
scale.
2.3.3 Stand by Fuel
i. Stand-by fuel for both boiler plant and emergency stand-by generators is 35s oil stored in two
dual skin storage tanks.
Storage volume is based on 4 days demand from the boiler maximum demand. Based on a
realistic assessment of normal winter demand it is estimated by Arup that a 10 day period will
be covered.
This is considered a reasonable approach as, whilst guidance suggests greater storage, it is
likely that a hospital will be treated as a priority customer and replacement supplies will be
readily available within this period without real risk. It is also reasonable to manage heat loads
in the event of interruption of the gas supply.
ii. It is intended to utilise the same oil storage to serve the electrical stand-by generators which is
a commonly used strategy as both loads use the oil infrequently and the oil is expensive and
deteriorates in storage.
iii. The total storage capacity was reduced from 4 tanks to 2 during the stage 1 value engineering
exercise. Space for the omitted storage is retained in the “grey box” i.e. space for future
replacement of the St James Hospital boiler plant.
iv. The overall provision of storage is considered practical and remains reasonably cautious when
considering the risk of failure.
2.3.4 Distribution
i. Heating distribution is a conventional flow and return system with multiple pumped circuits
serving various zones. This is a logical design for a development of this size and complexity
with various operational times etc. The separation of the various zones is as follows:
• Hot block (podium)
• North “fingers”
• South “fingers”
• Wards
• Domestic Hot Water generation
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ii. Control of the heat output of the various heat emitters is via 2 port pressure independent control
valves. This results in the distribution being a constant temperature variable flow rate design
philosophy and the various pump controls required to achieve this are incorporated in to the
design.
iii. The primary distribution is at basement level with a number of risers serving the various different
blocks and zones. This is a logical and conventional approach for large and complex buildings
with plant rooms at the higher levels.
iv. The main heating schematic shows potentially misleading flow rates of 150 Kg/s on the main
boiler header with 2 boilers at 60 Kg/s or 3 boilers at 60 Kg/s. This may reflect diversity in the
anticipated actual demand but should be clarified.
v. It is noted that radiant panels, fan coils and zone reheat batteries are all connected to a common
LTHW circuit which does not appear to be weather compensated. This approach is
unconventional but does not contradict guidance. The LTHW circuit is understood to operate at
constant temperature and 20o differential.
The omission of a compensated heating circuit was proposed to minimise costs, it is not clear
if this has been agreed and documented as a VE decision or accepted by default. It could be
argued that a compensated heating system would provide improved control and efficiency and
may be subject to future challenge and should be openly agreed by all parties.
vi. The complete heating piped services installation is noted on the drawings to comply with HTM
03-01 (Specialised ventilation for healthcare) which is assumed to be an error. It was considered
by Arup that HTM03 includes references to heating and cooling so should remain on the
drawings. This is not a risk and can be left as it is.
vii. A dedicated heat recovery circuit is proposed serving ward bedrooms and under couch heating
coils. This system runs and operates in parallel to and duplicates the general heating distribution
adding further expense to the complex ward bedroom ventilation strategy. The cost and carbon
reduction benefits of this system should be confirmed to ensure it is justified.
The Arup design analysis includes the provision of heating and cooling to the air intakes to
improve winter and summer temperature control and provide trimming of internal temperatures.
This is undoubtably beneficial and will result in improved internal conditions in ward bedrooms.
The provision of a dedicated heat recovery circuit remains questionable as this is duplicating
the general heating distribution and will only be a benefit when recovered heat is available.
2.4 Steam
2.4.1 System Configuration
i. Steam is provided for sterilising services and cleaning and is generated by 2 No. gas fired steam
boilers located in the basement plant room.
ii. The steam boilers include dual fuel burners that utilise gas as the primary fuel with oil as the
stand by fuel.
iii. Steam is generated by conventional steam boilers with clean steam for sterilisation generated
by intermediate steam to steam heat exchangers. This is a conventional arrangement
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iv. Arup advise that the use of electric steam generators was considered but discounted due to the
impact on the site electrical loads.
v. Some operational efficiencies may be achieved by the use of local steam generators matched
to the sterilising equipment and whilst this reduces the steam distribution the plant capacity is
duplicated.
Arup have confirmed that central steam generation was selected to minimise maintenance costs
and avoid the impact on the electrical capacity of local electric steam generators. As the
electrical loads are under pressure this is a sound strategy which is resilient and does not incur
unnecessary risk.
2.4.2 Boiler and Generator sizing
i. The steam boilers and clean steam generators are sized based on the arithmetic summation of
the demand from all equipment. This will probably result in oversized plant but is based on
advice provided by the sterilising operations team.
In reality some diversity will apply in use, and it would be assumed that some spare steriliser
redundancy is included to allow for normal operational down time. It must be recognised
however that it is difficult to establish accurate usage profiles as it is an unpredictable factor.
ii. Steam boilers are selected to give N+1 redundancy which is considered reasonable given the
critical nature of this service.
iii. When comparing the capacity of the clean steam generators with the feedwater system it
appears that the clean steam generators are selected on the basis of N+2 redundancy which
appears excessive. Arup should review this with a view to omitting one generator, whilst this is
not a significant cost saving it will assist in plant room access and coordination.
Arup have confirmed that a conservative strategy has been adopted due to the critical nature of
this service and that an instruction would be required to change the design. Clearly the decision
to reduce resilience would have to include the client and provide an acceptable level of security
of supply but there is an element of over provision in the N+2 strategy and in the lack of diversity
advised by the users. This strategy would merit some reconsideration.
2.4.3 Ancillary components
As the detail design of the steam and condensate is a Contractor design there are a number of
elements of the design that are not developed that could impact on the scheme and these are as
follows:
i. The provision of anchors, guides and expansion devices are not shown on the layout plans and
their inclusion will impact on the structure, access requirements etc. As these are contractor
design elements the Contractor’s BIM model should manage the spatial impact but there could
be knock on spatial and cost impacts on other services.
ii. The provision for line trapping of the steam mains is not shown on the layout plans and their
inclusion will impact on the access requirements etc in the basement corridors. As these are
contractor design elements the Contractor’s BIM model should manage the spatial impact but
there could be knock on spatial and cost impacts on other services.
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iii. The pipework arrangement for the take off from steam boilers and generators needs to be
reviewed to ensure that there is equal draw off from each piece of plant. If this is not the case
then operational problems can occur with loads that are switched on / off.
Arup have noted this to be reviewed with the specialist designers and should be monitored
during construction.
2.4.4 Condensate Recovery and disposal
i. Condensate recovery details have not yet been developed as this element is subject to
contractor design.
ii. Condensate recovery in steriliser installations is problematic for a number of reasons;
• Condensate from the primary side of the secondary heat exchangers is at high temperature
and will create flash steam which must be dealt with prior to return to the hot-well.
• Condensate discharge from the sterilisers is not recoverable and will be run to drain. The
high temperature discharge to drain and the potential for flash steam must be addressed.
This level of design is to be finalised by the specialist design/installer and will need to be
demonstrated to effectively address the issue of flash steam.
iii. The provision of relay points and the condensate generated is not defined on the Arup design
and is to be developed by the contractor. This may present coordination difficulties along the
distribution route.
2.4.5 Resilience and Maintenance
The system is resilient and reflects the critical nature of the sterilisation and cleaning processes for
the functioning of the Hospital. There are however some issues that could impact on the operation of
the system and these are:
i. The schematic drawings show a mix of single and double isolation on the steam system. There
is a need for Arup to review the maintenance risk assessment and Health and Safety legislative
requirements. We would recommend that all steam isolation points are a double block and bleed
arrangement.
Arup have confirmed that double block and bleed valves have been included in the specification
and are included in Spirax equipment. The specialist design and equipment selections should
be checked to ensure that the correct installation is maintained throughout.
ii. The provision of single blowdown vessels is a potential single point of failure for the steam
system and these vessels do need to be taken out of service for annual insurance inspection.
The blowdowns can be manually managed during this time so providing the risk is fully
understood a second vessel on each system may not be necessary.
The Arup strategy relies on a managed operation which is viable if the maintenance team
understand and accept this approach.
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2.4.6 Contractor’s Design Proposals
It is noted that the steam system is included as a contractor design package and whilst this is perfectly
reasonable it means that final coordination cannot be completed until the contractor’s design
proposals are concluded.
It is understood that proposals are available and have been requested for review. The Contractor
design proposals have not yet been reviewed and could be subject to a more detailed follow up review
if required.
2.5 Water and Drainage
2.5.1 Water Supplies
Dual incoming supplies are included to feed dual bulk storage tanks. Additional connections feed
sprinkler and hydrant storage tanks.
At stage 2b recovery of RO waste water was dismissed as the use of borehole water was proposed.
As the use of bore hole water is no longer included has the recovery of RO waste water been re-
evaluated?
Arup have confirmed that the recovery of waste water from RO plant has been considered but rejected
due to cost and high salt content of the recovered water.
The use of borehole water is considered a false economy due the treatment required and also requires
a back-up supply from the town mains which creates the risk of a stagnation if unused. As resilient
supplies are available this is considered the favoured solution.
It is understood that rainwater harvesting is excluded due the inclusion of green roofing. Whilst the
introduction of rainwater harvesting could be applied the cost of the separate system and treatment
required is prohibitive.
Similarly, the application of grey water harvesting has been excluded. Whilst grey water harvesting
could be seen as environmentally sound its use in hospitals is generally seen as inappropriate.
2.5.2 Storage Volume
i. Primary storage includes dual tanks totalling 500m3 storage.
ii. Based on approximate bed numbers of 380 (as stated in the stage 2b report, actual numbers to
be clarified) hospitals would typically use 450 L/bed/day resulting in a total storage requirement
for 24 hours of approximately 171,000 L
iii. It must be recognised that as this is a children’s hospital the accommodation provides for
parents to stay with children thus increasing (arguably doubling) water usage.
It must also be recognised that for the total area of the building bed numbers are low. A typical
hospital of this size would be expected to have in excess of 700 to 800 beds. Allowing for the
additional clinical and laboratory area would also increase water use beyond the norm/bed.
It is plausible therefore to assume that the total daily water use could be as high as 500m3
however this is considered high.
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iv. It is considered reasonable to allow for half of one day’s storage given reliability of water
supplies and the embedded resilience. It must be noted though that Dublin City Regulations
require 24 hours storage.
HTM 04, clause 8.5 recommend stored volume should be based on 12 hours storage whilst
acknowledging that calculation of daily usage is not an exact science and suggests seeking
advice form operational hospitals.
Reference is included to 900L/bed/day as too high and whilst it has to be recognised that this
hospital contains disproportionately few beds for the area, as noted above, this suggests the
present stored volume may be excessive.
The total daily water usage should be reassessed to ensure excessive storage is avoided as
this increases the risk of bacteriological growth and stagnation.
v. Additional separate storage is included for sprinklers and fire hydrants.
vi. Arup have submitted the water storage assessment for comment and this demonstrates the
methodology for the volume a storage provided.
The basis of calculation is 600 L/bed/day (the summary schedule shows 599 which is not
explained but this is not significant) allowed for a total of 520 beds.
Clearly the definition of a bed in this context is open to some interpretation and various numbers
have been quoted for the bed count, however for purposes of calculation the higher figure
should be used.
The calculation also allows for additional storage allocated to staff usage, which for a building
such as NCH which includes disproportionately few beds for the area this is understandable,
however the total of 600 L/bed/day includes an allowance for other general usage. Also, the
figure of 600 L/bed/day is an historic usage and is generally less in modern hospitals.
It is confirmed that the stored volume reflects the DCC requirement for 24 hours storage.
In conclusion it is considered beneficial to reduce the volume of stored water to improve turnover
and minimise the risk of temperature increase and bacteriological growth, whilst providing
satisfactory reliance in the event of an interruption to supply.
The basis of reduction should reflect consideration of 12 hours storage and recalculation based
on more realistic consumption data. Arup have suggested comparison with other hospitals in
the area to verify actual usage which would be good evidence of real consumption figures.
2.5.3 Segregation of risks
i. A separate non-potable water system is provided to serve lab areas considered to be a category
5 risk.
ii. Dedicated duplicate water storage tanks incorporating the required air break, are included to
the non-potable supply.
iii. A dedicated, untreated drinking water supply is taken to kitchens where baby feeds are
prepared.
iv. It is noted that the design of the irrigation system including plant and pipework is to be completed
by a specialist contractor. The performance parameters of this system have not been received.
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v. Hose union bib taps are specified to be fitted with double check valve assemblies. The
adequacy of a double check valve is dependent on the risk category and generally hose taps
are considered as a category 5 risk requiring an air break.
It is noted that the irrigation package is not part of Arup MEP scope and is being procured
through BAM, however the provision of backflow protection must be maintained.
2.5.4 Booster arrangements
i. Water distribution is via a single multi pump booster set and whilst this allows redundancy of
pumps a packed pump set relies on a number of common components, particularly the control
panel which is one of the high risk elements.
ii. It is suggested that consideration be given to duplicate pump sets sharing the duty which will
improve resilience and controllability.
iii. It is agreed by Arup that provision of duplicate booster sets would improve resilience of the
water system however an instruction would be required from NPHDB to change the specification
of the pumps. As a minimum it should be ensured that pumps can be operated in a manual
override in the event of faults on the controls.
2.5.5 Hot water generation
i. Domestic hot water is generated in 4 locations, 3 covering the main hospital and a fourth serving
kitchens. This approach avoids excessively large distribution and results in a more manageable
installation.
ii. Each hot water generating station includes duty/standby plant allowing for proper maintenance.
Consideration could be given to duty/support/standby to improve resilience and flexibility but
benefits are limited and costs higher.
iii. It is noted on the drawings that “where hot water is thermostatically controlled” a warning notice
stating “very hot water” should be fixed. This is a typing error and should refer to where hot
water is not thermostatically controlled?
2.5.6 Hot water circulation
i. Hot water temperatures are maintained by means of conventional return circulation systems.
ii. Regulation of the system flow is by means of temperature balance with the use of temperature
sensing valves. These have a minimum flow rate requirement that Arup advise has been
accounted for in their hot water return pump and pipework sizing.
Whilst the use of temperature controlled regulating valves result in a higher than necessary
return flow they are an effective means of control which ensure that all parts of the system are
subject to circulation and water temperatures are maintained. Commissioning costs are also
minimised and the process made manageable.
2.5.7 Legionella Management
The facilities within the design to assist the management of legionella within the hot and cold water
systems is as required by design standards and guidance. This is principally covered in the following
provisions:
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i. Temperature monitoring of the cold water storage temperatures and hot water generation
temperatures.
ii. Facility to pasteurise the hot water system, should be confirmed in contractor’s proposals for
the BMS. Arup have confirmed that pasteurisation provision has been included.
iii. Minimising cold water dead legs by configuring pipework routes to have WCs at the furthest
point.
iv. Installation of flushing valves at key points in the cold water distribution.
v. Provision of UV treatment where appropriate.
The control of the risk of legionella bacteria growth is achieved in part by design and in part by
diligence in the maintenance and operation of the systems and the current design provides adequate
facilities for the maintenance of the systems.
A drain point is specified at all low points on the hot and cold water systems. The installation of a drain
cock at a low point will inevitably collect any debris in the system and become a potential breeding
ground for bacteria and should be avoided where possible.
Arup have agreed that the provision of drain cocks on water services systems is to be limited in so far
as is possible however it is noted that some will be required but these should be minimised where
possible.
2.5.8 Oculus Consultancy Report and NPHDB Response
i. The Oculus report refers to the introduction of proportional dosing of the water supply which
was not then included in the design. Arup’s response recognised the benefit and suggested this
would be added. It is not clear if this has been done, but would be expected if a follow up review
was carried out by Oculus.
ii. The report refers to supplying irrigation tanks from a non-potable system via an RPZ valve. The
Arup design does not include this approach as there is no non-potable system. If a non-potable
system were to be included the irrigation system should retain the break tank to maintain
separation of hazards. The proposed design is compliant as required.
iii. The report refers to dosing of the peak water flow whilst the Arup proposal is to dose the
incoming make-up water, hence dealing with a lower flow rate. Sizing the dosing equipment for
peak flow is noted as impractical and prohibitively expensive by Oculus so seems a strange
suggestion. The Arup design proposal is compliant.
iv. The use of UV at source is not advocated by the report and not recommended on drinking water
outlets due to thermal gain. Arup appear to be retaining the UV treatment but are proposing the
addition of filters to the Zip water boilers. If not already included this will add cost, however the
Zip boilers generally include filters. This should be checked and concluded.
2.5.9 Drainage Systems
i. The internal drainage designs have been developed to stage 2C for completion to installation
stage by the contractor. The drawings are detailed and fully define the installation. Provision of
supports and bracing is left to contractor design as would be expected however this leaves the
contractor to ensure that adequate falls are achieved and in congested areas this has often
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resulted in a compromised installation. Careful monitoring should be carried out to ensure the
correct installation is achieved to avoid the future risk of blockages.
ii. Acoustic treatment is specified over “sensitive areas” although it is not clear which areas are
considered sensitive. Such areas should be clarified and not left to the judgement of the
installer.
iii. The location of gullies at basement levels and the connection of stacks to below ground
drainage is stated and “indicative” with the final coordination left to the installer. This is a risk
item which should be avoided or at least carefully monitored.
iv. Stub stacks with rodding access on top are noted, suggesting that these are unvented. Care
must be taken to ensure that all parts of the system are adequately vented. Arup have confirmed
that
v. Foul water falls of 1/100 are specified in car park areas, if only surface water this is acceptable
but if foul waste falls should be greater and in accordance with BS12056. Falls elsewhere are
specified as 1/40 which could be reduced that specified in BS 12056
Arup have confirmed compliance with BS 12056 but it must be recognised that reducing the
falls on any drain runs will increase the risk of blockages and should be avoided. This comment
applies to any drains and not just local branch pipework.
2.5.10 Drainage Materials
i. Fouls waste stacks are generally specified as cast iron although certain stacks in the “fingers”
are excluded. UPVC is specified for stacks in the fingers unless specifically noted as cast iron.
The reason for the change of material is not clear but the use of PVC, whilst compliant with
standards, is not recommended for stacks in clinical areas.
Arup have confirmed that the selection of UPVC for stacks in the fingers are considered
acceptable due to the reduced building height. This decision is compliant with standards and is
driven by the need for cost reduction, however after fire stopping and acoustic treatment is
considered the cost reduction is likely to be small and risk of damage in service remains.
ii. Down pipes in the basement car park are specified as cast iron, which is considered ideal, or
alternatively copper, stainless steel or Vulkathene. These are all acceptable materials, subject
to jointing methods, but care should be taken if light weight stainless steel systems are used as
corrosion has been documented with some cleaning products, particularly in vent pipework.
iii. Foul Waste pipework in rooms is specified as UPVC which is appropriate for connections from
sanitary fittings but bust be clear that this does not apply to stacks or main drain runs in ceiling
voids.
iv. UPVC is specified for soil vent pipework which is appropriate subject to the inclusion of fire
collars at all penetrations of fire barriers.
2.6 Medical Gas installations
i. Medical gas installations are subject to contractor design by the specialist although Arup have
developed the concept designs upon which the specialist designs are to be based.
ii. The specialists design proposals have not been received for review and it is assumed that as
an accredited specialist will carry out the design and installation there should be little risk of
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non-compliance. It is assumed that Arup will have a monitoring role on the medical gas detailed
design.
iii. It must be recognised that as the medical gas specialist’s designs are developed there may be
a necessity to accommodate additional AVSUs and alarm panels which will need to be
coordinated with the room layouts. This should be monitored and will require the coordination
of the architects.
iv. It is noted that the medical gas proposals have been reviewed by the hospital AP and no
adverse comments received.
2.6.1 Oxygen
i. Oxygen supply the NCH site is via a ring main with the primary source of supply being a new
VIE installation located on the NCH site.
ii. The supply is also connected to the St. James distribution which is served by a second VIE
installation. The second VIE is not sized to adequately supply both sites and the pipe link
between the sites connects to the St James distribution at a point which does not have the
capacity to serve the NCH demand.
iii. A third, temporary VIE installation has been installed on the St James site but it is intended to
remove this installation when the new NCH VIE becomes live.
iv. Whilst the arrangement proposed complies with the letter of HTM 02 in providing alternative
supplies it appears that in the event of a complete loss of the NCH VIE supply oxygen supplies
may not be adequate from the second VIE.
This should be reviewed and the adequacy of the second source of supply confirmed.
v. It is noted that a standby manifold installation is not included as this would be impractical in
operation. This approach is considered normal and acceptable.
vi. The resilience of the proposed strategy has been discussed and the risk associated with an
inadequate secondary supply and undersized link to the St. James VIE is not considered
acceptable given the critical nature of this service. It is recommended that the temporary VIE
installation and pipe link be retained or relocated if possible. An alternative would be to increase
the capacity of the St James VIE and interconnecting pipework.
2.6.2 Nitrous Oxide
i. Nitrous oxide is included in the project although this is very often omitted from new hospitals. It
is understood that the gas has been confirmed as required by the users.
ii. Nitrous oxide is supplied by a duty/support/standby manifold installation in the basement
plantroom in accordance with HTM02
iii. Nitrous oxide has been provided to Critical Care rooms in addition to the more usual areas.
iv. It is noted that low level extract ventilation is provided to all areas where nitrous oxide is used.
2.6.3 Entonox (Nitrous Oxide/Oxygen mix)
i. Entonox is included in the project, supplied as nitrous oxide from a manifold installation in the
basement in accordance with HTM 02
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ii. The provision of low level extract ventilation in areas where Entonox is used is yet to be verified.
Arup have confirmed that low level extract is provided in all locations where Entonox is used.
2.6.4 Medical Compressed Air
i. A central medical compressed air plant, located in the level 3 plant room, incorporating multiple
compressors is proposed to provide the resilience required by HTM02.
ii. The compressor plant is supported by an emergency standby manifold located in the basement
plant room where delivery of replacement cylinders can be properly managed.
iii. It is noted that the medical air system is completely separate from the surgical air system. HTM
02 permits the use of combined systems, with pressure reducing sets, which could improve
resilience by sharing multiple compressor plants. The proposed arrangement is not non-
compliant however and may be preferred operationally.
iv. Medical air is supplied to all ward bedrooms and, as this is not mandatory in HTM 02, is
assumed to be required by the brief.
2.6.5 Surgical Compressed Air
i. A surgical compressed air system in included derived from a dedicated simplex compressor.
Whilst compliant with HTM 02 this is unusual on a project of this size and multiple compressors
would be anticipated.
The specialist designer will address this selection based on the most appropriate solution.
Arup have confirmed that the actual plant selection includes duplex compressors as would be
anticipated.
ii. The provision of a standby manifold installation is yet to be verified.
2.6.6 Medical Vacuum
i. A central medical vacuum plant, located in the level 3 plant room, incorporating multiple vacuum
pumps is proposed to provide the resilience required by HTM02.
2.6.7 Laboratory Gases
i. Specialist laboratory gases are also included but these installations are yet to be reviewed.
ii. It is understood that there are no explosive gases included in the project, and has been
confirmed by Arup.
The internal medical gas distribution, valve and alarm arrangements have not been reviewed
and will be defined on the specialist’s drawings. It is anticipated that these will be reviewed by
the medical gas AP but a further review can be carried out if required but should not be
necessary in addition to the AP comments.
2.7 Building Management System
i. It is understood that the BMS installer has been selected to be Ashdown Controls, a systems
house for Cylon controls.
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ii. The scale of the project and the capability of Ashdown to manage an installation of this size has
been a cause for concern and given the critical nature of the controls installation in the
successful operation of the M&E systems this presents a significant risk.
It is also recognised that the installation and commissioning will be phased reducing the
magnitude of the task at any point in time.
iii. In order to address the risk of project scale assurances have been sought and received by Arup
that Cylon will support Ashdown on the project, on the basis that Cylon will supply the hardware.
Whilst the support from Cylon provides reassurance, the commissioning of the controls
installation remains a project risk and management of the phased completion will be essential
in achieving a successful completion.
iv. It is understood that Ashdown have produced a schedule of deviations from the Arup
specification which has not been received for review. Arup are challenging non compliances but
with cost pressures it would be tempting to accept a reduction in specification and this should
only be done with the long term operation and maintenance in mind.
Arup have confirmed that they will not accept non-compliant items unless agreed with
NPHDB/CHG with associated cost savings and evidence of compliance challenges observed
to date support this view.
v. Control valves are to be supplied and installed by the mechanical contractor who is offering
alternatives to the specified equipment which Arup do not consider compliant. Arup are
expecting, as specified, that the BMS specialist will verify the valve selections however the
contractual arrangement between mechanical contractor and BMS specialist will be difficult to
control and reliance on this may prove difficult.
vi. With regard to operation of M&E systems under generator start-up and potential generator
failure the BMS will be required to manage the sequence restart and load shedding of plant.
Sequenced start and load shedding have not been fully resolved and is not fully included in the
BMS specification at present.
Arup are to review the strategy to confirm operational requirements and have referred to
NPHDB/CHG defining plant priority schedules. Whilst the client team will need to be involved in
such discussions it will of necessity be a joint exercise and would be expected to be led by the
designers.
vii. The number of alarms being generated on to the BMS and how these would be managed was
discussed. Arup advised that the provision of alarm categorisation is included within the BMS
specification but the exercise to categorise alarms has not yet been carried out. This is a critical
activity for the Hospital FM team and needs to be done in a timely manner with their input.
As above Arup have referred to NPHDB/CHG defining plant critical alarms. Whilst the client
team will need to be involved in such discussions it will of necessity be a joint exercise and
would be expected to be led by the designers with the FM team involved along with the client.
2.7.1 Performance Documentation
We have carried out an initial review of the documentation prepared by Arup and have not identified
any areas for concern with regard to compliance or over engineering. The system specified and the
system architecture is expandable to accommodate the 20% expansion required by the Brief.
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The use of a separate Energy Management System for the is not unusual and should not attract
additional cost.
2.7.2 Control Strategies
The control strategies set out in the Arup design are those required to achieve the required control of
the various systems. There are additional sensors included around heater batteries etc that monitor
the performance of the systems which could be considered to be excessive but if they were omitted
then commissioning and fault finding would be more difficult and hence costly.
In summary the provision is robust and has been designed to simplify the on-going operation of the
building rather than drive to the lowest initial cost.
2.7.3 Contractor’s Proposals
During the review meeting we had sight of some pages of the Contractor’s Proposals prepared by
Ashdown who are the specialist Sub Contractor to BAM. We need to have access to that
documentation in order to fully comment.
We have since received a Technical Submittal document NPH-X-JEG-SB-XXXX-0085 on 11/09/18
containing Ashdown's high-level submittal for the BMS and offer the following comments: -
i. The Cylon Letter of Product Support provides assurances that Cylon Controls Ltd will supply
and support a list of Cylon products, including software support to Ashdown Controls Group. It
also states that Cylon are an 'Authorised Tridium Reseller' licensed to purchase, distribute and
support Tridium hardware and software products. More clarity should be provided with respect
to the level of on-site technical support provided to Ashdown's, particularly in relation to the
integration of other services containing other protocols.
ii. The Ashdown letter of BMS Product Purchase confirms that all BMS hardware items and
Software packages will be purchased from Cylon Controls but is unspecific with regards to the
actual product references. More clarity is therefore required.
iii. The conformity schedule contains a check/tick list stating compliance with the clauses indicated
in section 5 of the Arup specification. Many of the components on the first sheet are associated
with the Tridium Jace controllers and Cylon BACnet controllers for compliance with the Niagara
4 framework operating platform. Whilst the clauses have all been ticked for full compliance,
there is some ambiguity associated with the 'native BACnet' terminology and if all Cylon
controllers are 'native BACnet' or only the CBX ones and also if the Tridium Jace 8000
controllers are native BACnet.
iv. This is highlighted by the comments under clause 5.4.1 to 5.4.3. but not for other controllers.
v. The Arup specification calls for the 'controllers, servers and workstations to communicate
natively via ASHRAE/ANSI Standard 135-2012 BACnet protocol' under clause 2.1 suggesting
all controllers should be native BACnet. Arup have confirmed this is the case but equipment
selections will need to be monitored to ensure that full compliance is achieved in order to
maintain the operational aspirations of the systems.
vi. There is no conformity schedule for the other clauses contained within sections 1 to 4 of the
Arup BMS specification – only for section 5.
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vii. The Arup specification calls for the BMS to be capable of CFR 21 Part 11 compliance under
clause 2.1 (although it states 'not required day one') There is no statement contained within the
Ashdown Technical Submittal about the system being compliant with 21 CFR Part 11. The
standard relates to Electronic Records and Electronic Signatures and is generally a requirement
for validation purposes associated with the Pharmaceutical and Food Industries, therefore
further clarity is required in relation to its purpose for NPH.
It is thought that this may have related to requirements within the labs, pharmacy and turn key
areas and therefore is specified throughout. Arup have committed to review this requirement
and clarify the specification.
viii. To the best of our knowledge, and from experience with pharmaceutical manufacturers, the
Cylon equipment is not compliant with 21 CFR Part 11 and only the Siemens Desigo BMS
product has certification for compliance with this standard.
ix. The conformity schedule columns which have been populated with N/A presumably relate to
components that are not required for the NPH project, namely wireless temperature sensors
(5.7.3.3), glass surface temperature sensors (5.7.3.9), electric meters by electrical contractor
(5.7.11.1) and thyristor controllers (5.7.12). The introduction of wireless temperature sensors
could be considered as a cost saving / value engineering measure, particularly for non-critical
local sensors or monitoring sensors.
Arup have considered wireless sensors and believe hardwired sensors more appropriate for
this project. They believe wireless sensors can be problematic and require additional
maintenance, are more expensive and it is unlikely that full installation cost savings would be
achieved.
This approach is accepted and would be worthy of further reconsideration.
x. There are many components on the conformity schedule (from page 2 onwards) which state
'device submittal to be issued' in the comment's column albeit that the compliant column states
'yes' and has been ticked. – how is it determined that the devices are compliant without a
technical data sheet to accompany it? Further clarity is therefore required.
xi. Arup Notes are listed 1) to 11) on their document review, however the Conformity Schedule
only indicates notes 1) to 7) – it appears that some sheets missing from the conformity schedule
and this should be reviewed completed.
xii. We generally agree with the notes 1) to 11) issued by Arup.
2.7.4 Observations Related to Performance Specification
The following observations highlight areas in the performance specification which may be adding cost
to the BMS and potentially could be 'value engineered' to offer cost savings without compromising the
functional operation of plant. Other points relate to clarification of interfaces and functionality.
i. Clause 2.3.9. calls for touch pad display panels on the fascia of each local control panel LCP
which are de-centralised for every AHU and likely to be within close proximity. This potentially
could be reduced to one touch screen display panel per plantroom since the systems are
networked over I/P and can be accessed from one location.
Arup have agreed that this will be further reviewed to see if worthwhile savings are available.
Generally, the specification is intended to achieve resilience so that if network fails visibility is
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available locally for each system. This is a sensible approach and unless significant savings are
available the design intent should be maintained.
ii. Clause 2.3.11 requires the BMS Specialist to select and supply all the motorised control valves,
valve bodies, actuators and PICV's as a complete unit including cranks, linkages and mountings
etc. This is the preferred method of procuring the control valves as it places the onus of
responsibility firmly with the BMS Specialist for sizing and selection. However, as mentioned
earlier in this report, the mechanical contractor is offering a lower cost alternative whereby they
supply and install the valve body but the actuator is by the BMS specialist. In our experience,
this alternative is unreliable with respect to demarcation point and levels of responsibility and
can ultimately compromise the control valve authority.
iii. Clause 3.4 requires the frost coil to be controlled at a minimum of 10°C. This should be set
lower at around 5° for ventilation systems equipped with heat reclaim to maximise efficiency.
Arup have agreed that the lower setting would be desirable and acknowledged that this is a
variable setting which is easily controlled. The operational parameters should be confirmed to
the contractors to ensure the correct settings are included.
iv. Clause 3.9 calls for all filters to be monitored by differential pressure sensors as per the HTM
requirement. These analogue devices are costly particularly when applied on every filter
throughout the building. A sensible derogation would be to provide simple differential pressure
switches (digital inputs) for monitoring the filters on AHU's serving non-clinical and non-critical
areas, for instance wards and offices.
Arup have agreed with the comment but have stated however that sensors allow gradual filter
aging to be monitored rather than simply a filter dirty alarm function provided by switch. Whilst
more expensive it is acknowledged that this as a desirable function and should be retained
unless drastic cost savings are required.
v. The staggered start routine under clause 3.21 could be simplified due to the vast majority of the
fans and pumps having (VSD) inverters and therefore essentially soft start.
vi. EC motors could be considered on AHU plug fans in Lieu of traditional (VSD) inverters offering
better efficiencies and less maintenance due to brushless motor technology. This is probably
only applicable for AHU's with smaller volume requirements.
Arup have confirmed that EC motors are being provided where absorbed power of fans allow,
otherwise VSD’s will be provided.
vii. The (VSD) run and fault status could be transmitted through the direct BACnet interface with
the frequency inverter reducing the number of hardwired points. The enable and speed control
signal should remain as hardwired for safety interlocking. A derogation from the HTM would
need to be sought as 'Run' and 'Fault' lamps are required at the control panel – not just the
BMS.
Arup have considered this provision and prefer to maintain the stated design intent. Whilst more
expensive it is acknowledged that this as a desirable function and should be retained unless
drastic cost savings are required.
viii. Emergency Stop Push Buttons are specified for all motive equipment under clause 3.26.4 which
are connected directly into the Variable Speed Drive (VSD). This is for compliance with the
machinery directive and not usually provided for (HVAC) plant in the UK.
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ix. The local zone reheat batteries are specified with drip tray leak detectors under clause 4.7.1 as
per HTM requirements. It appears that the BMS package includes leak detection to all reheat
batteries however the catch tray and leak detection provision has been reduced to those heating
coils located over occupied areas. The actual scope included should be verified. – The scope
could be reduced by ensuring the zone re-heaters are located in the corridors and away from
patient areas to negate the requirement for drip trays.
Arup have committed to review this provision. Leak detection was removed from a number of
batteries (those not over bedrooms) as part of the previous value engineering exercise but this
does not appear to have been captured in the BMS specification.
x. The control of the naturally ventilated bedroom with under bench coil described under clauses
(4.10.1 to 4.11.2.2) is elaborate and complicated, particularly with the dual function
cooling/heating panels and thermal demand feedback influence on the centralised AHU
ventilation plant on the supply air reset. Is there scope to simplify the controls strategy?
Arup have, as noted above under ventilation, committed to review with NPHDB/CHG when the
mock up room is complete. The intent is to give patient control with reset to ensure minimum
fresh air is delivered. This is noted and the final control strategy must be clearly defined in the
operational manuals and be clearly explained to ward staff.
xi. The volume sensors required for each AHU in the fan's integral inlet bell mouth described under
clause (4.13.1) for volumetric flow is costly when applied to every AHU. A derogation could be
sought to reduce this to Operating Suites and Laboratories only where volume control of the fan
is required. Non-clinical AHU's and ward area AHU's do not require volumetric flow control for
control purposes unless they are for VAV applications.
Arup happy to consider this subject to sign off from NPHDB/CHG but do not intend to change
the current scope. It is acknowledged that this as a desirable function and should be retained
unless drastic cost savings are required.
The leak detection (4.13.1) on critical AHU's Type B, Type C and Type D appears to be over
engineered for detecting a possible burst coil. Could this be done by alternative means such
as a pressure detector on the common LTHW circuit per plantroom?
Arup have confirmed that the requirement for leak detection in critical AHU's come from HSE
AHU specification. Arup happy to reconsider this subject to sign off from NPHDB/CHG but this
should be retained unless drastic cost savings are required.
xii. The interface with the lighting management system is utilised for PIR operation of HVAC
terminal units and zone control requesting 'read-only access required for day one' however
read-write possible for any point. (Clause 4.28.1). The read-write function is a higher level of
integration which will involve more engineering time and site commissioning if adopted.
Arup have agreed that read only access is required and will modify the specification to clarify
the scope to be provided.
xiii. The BACnet / IP interface with the Motorised Smoke Fire Damper System requires to have the
functionality to close the SFD's leaving the plantroom upon detection of smoke-in-duct on the
supply air from each of the AHU's (HTM requirement). Clarification is required in relation to
where the duct smoke detector is connected to, and who is supplying this device as it is not
detailed in the BMS performance specification.
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Arup have confirmed that the in-duct smoke detector is included in the electrical specification.
It is assumed this is provided via the fire alarm system which would be unusual as this is a direct
link to the air handling plant and BMS. The operation of the detector should be verified during
commissioning.
xiv. Consideration to the application of Zigbee wireless temperature sensors (Clause 5.2.2) on the
local floor areas could be utilised which is a resilient mesh system and may offer substantial
cost savings.
2.8 Equipment and Systems Specifications
2.8.1 Equipment Schedules
Equipment data sheets have been produced by Arup for the mechanical and electrical equipment.
The data sheets include the performance requirements and specifications of each item of equipment
and based on our reviews we have no significant concerns relating to the equipment specifications.
2.8.2 Proposed Manufacturers
The manufacturers, where defined, do not generally give particular cause for concern. Arup
specifications do not generally define manufacturers with selection by the contractor with review and
comment by Arup.
It is understood that the air handling unit manufacturer has been challenged by Arup and following
investigation and assessment has been generally accepted, although CHG have commented that this
is subject to the judgement of the design team and final performance tests.
Arup have also challenged the contractor’s selection of pressure independent control valves which is
yet to be concluded.
It appears that the process is maintaining the required quality standards although as costs are under
pressure there may be pressure to compromise.
3 ELECTRICAL SYSTEMS
3.1 Electrical Infrastructure and Resilience
3.1.1 Incoming Supplies
i. It is noted that the Children’s Hospital is provided with dual incoming supplies albeit from the
same ESB network. It would improve resilience if supplies could be arranged from separate
ESB substations however this is a standard ESB approach and will not be changed.
ii. The 2 number ESB supplies enter the building via diverse routes via an A & B switchboard
connected by a bus coupler with automatic changeover. Both supplies and A & B boards will
carry the full load of the building. There is however only a single cable supply to the Hospital
10kV switchboard and this is a single point of failure.
The designers have sought to change this but this is an ESB requirement to meter one supply.
The risk has been managed by keeping this single supply cable as short as possible and it is
contained in a controlled area. This situation is standard for ESB and cannot be changed and
all reasonable precautions have been taken to manage the risk.
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3.1.2 Stand by Generation
i. Emergency standby generation is provided via 5 No. 2.5 MVA prime rated generators giving
N+1 redundancy on the declared maximum demand. This is equivalent to 8 MW of generator
capacity which is consistent with the incoming supply arrangements.
ii. Space provision is included for a 6th generator to serve the 20% expansion space.
It is assumed that the Maternity Hospital will be provided with dedicated stand-by generators
consistent with the dedicated electrical intake, and will not be reliant on the Children’s Hospital
generators.
iii. Protection arrangements for the generator installation are provided, it is observed that general
requirements for protection relays are provided within the specification, but the details do not
indicate if non-directional, directional, reverse power, G10 requirements for paralleling with the
mains, etc.
iv. A protection grading study for the MV and LV electrical network when operating on the
generators in island mode has not been provided for review. The designers are to carry out an
HV/LV Grading Study when ESB protection settings and final selection of switchgear and
protection relays received.
v. The PMS specification indicates that any load management under plant failure will be developed
by the PMS Specialist. We see this as a significant financial and programme risk to the Contract.
The Specialist will be unable to develop this strategy without a detailed knowledge of the
distributed loads around the hospital, the critical nature of the loads, and the priority each load
should be given. This information will not be available to him when he is producing his tender.
Therefore, any development of this element of the works will have cost programme implications,
and further cost and programme implications to other systems that will need to accommodate
the load management requirements.
The PMS system and load shedding strategy to be further developed by the designers.
vi. The PMS does not reference IEC 61850 as a principal design standard. This is an important
document that is referenced elsewhere in the specification and facilitates fast communications
and control functions via GOOSE messaging. This facility will be required for the PMS.
Designers have confirmed that the PMS Contractor has allowed for IEC 61850 compatibility and
for the application of Goose Protocol.
3.1.3 Sub Stations
i. A total of 7 sub-stations are provided at;
• B2 North
• B2 South
• LG North
• Level 3 N & S
• Level 7 N & S
All sub-stations incorporate dual transformers, each rated at 100% of connected load giving
N+1 redundancy at each location.
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Transformers are cast resin and are located internally.
3.1.4 UPS
i. UPS installations are provided to serve;
• Medical group 2 locations
• IT installation
ii. UPS installations are rated as N+1 with each capable of covering the full load. Each UPS is
served from different transformers to maintain the N+1 resilient arrangement.
iii. Medical UPS provides 1 hour autonomy on the basis that critical supplies will be reinstated by
generators within 15 seconds. An additional derogation required to clarify battery autonomy of
1 hour for medical systems when generators will not be available within 15 seconds.
iv. IT UPS installations provide 15 minutes autonomy which has been agreed as acceptable.
v. Medical UPS supplies IPS units serving group 2 medical locations but also serve “essential”
supplies in those areas not connected to IPS circuits.
vi. This is not considered mandatory and is a cautious interpretation of regulations however it is
considered a reasonable and sensible approach for a digital hospital and has minimal cost
implications.
3.1.5 IPS
i. Isolated power supplies are provided to group 2 medical locations as defined by the wiring
regulations.
ii. IPS circuits are included to operating theatres, critical care areas and haematology/oncology
ward procedure rooms. The final schedule of areas served is yet to be reviewed.
iii. IPS units are interlaced between areas to improve resilience.
3.1.6 MV Distribution
The MV schematic revision CO2 has been reviewed.
i. It has been confirmed that the schematic arrangement of the MV distribution has been revised
and will be reissued to 4P for comment. This has not been further reviewed
ii. The anticipated electrical maximum demand of the Hospital is stated as 8 MVA which includes
an allowance for spare capacity. Currently 8 MVA is the maximum demand that the ESB can
accommodate. It is thought that 10 MVA may be possible however 8 is declared as the
maximum.
Based on typical hospitals of a similar scale the anticipated maximum demand (including spare
capacity) would be approximately 7.5 MVA which suggests the 8 MVA quoted is realistic but
not overstated.
The analysis of the building loads has been reviewed, and benchmarked against other similar
projects. Whilst the loads allowed by the Arup design are at the upper range of typical hospitals
they are consistent with other projects. It must also be recognised that the NPH is a clinically
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intensive hospital with fewer bed for the area than a typical DGH hence the loads would be
expected to be at the higher end of the range.
iii. A CHP set, rated at 1800 kVA is included to satisfy the low carbon aspirations of the client. The
CHP is not included as emergency stand-by capacity and would not run in the event of mains
failure and has not been deducted from the site supply capacity.
This is a compliant and standard approach as CHP cannot be guaranteed to be available at all
times or in the event of an emergency.
iv. The routing of the MV distribution to sub stations within the Hospital is segregated in to A & B
services which follow diverse routes and are within different fire compartments. This is in
accordance with HTM requirements.
However, during the review of the basement, it became apparent that changes to the building
layout had caused some fire compartment boundaries to move and for A&B cables to now be
in the same compartment. Arup agreed to review the cable routing to ensure that the integrity
of the fire separation was not compromised and discuss further with the Design Team.
v. No protection details for the MV network are provided, it is observed that general requirements
for protection relays are provided within the specification, but the details do not indicate if non-
directional, directional, reverse power, G10 requirements for paralleling with the mains, etc.
refer to item vi.
vi. A protection grading study for the MV and LV electrical network has not been provided for
review. The designers are to carry out an MV/LV grading study when ESB settings, switchgear
and final selection of protection relays known
3.1.7 LV Distribution
i. The fire protection requirements of electrical distribution have been recognised with distribution
cables following diverse routes and within separate containment. In addition, fire rated cables
are provided for life safety supplies.
Review of the cable containment drawings would indicate that generally diverse cable routes
have been provided, however, there are locations within the building that would appear the
diverse routing has been compromised. It is not possible to confirm the affected areas as
definitive cable routes are not detailed on the drawings, only general containment routes.
Diverse routing should be reviewed by the designers and discussed further with the Design
Team.
ii. It is noted that 3 pole isolation has been provided to a number of switchboards with dual
supplies. We would expect 4 pole isolation at these locations. The designers to review and
consider alternative neutral earthing arrangement for UPS unites. i.e. neutral earth contactors
or isolation transformers.
iii. It is noted that the transformer LV ACB’s are 3 pole devices. We would expect 4 pole isolation
at these locations. The designers to review and consider alternative earthing arrangements for
UPS units, i.e. neutral earth contactors or isolation transformer.
iv. All STS and ATS devices should be 4 pole units, this is not clearly defined on the LV schematic
diagrams. Designers confirmed that all STS and ATS units are 4 pole devices.
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v. The LV schematics indicate a number of 4 pole devices that appear un-necessary, and 3 pole
would suffice. Refer to attached, marked up drawings.
vi. It would appear that there are no local transfer switches at each set of distribution boards,
therefore should a busbar be taken out of service certain supplies would be lost. Designers to
review this single point of failure with the client and consider providing changeover facilities at
each departmental distribution board arrangement and possibly removing the static transfer
switches at the base of each busbar.
vii. Switchboard MPB-WD-07-002, 002A and 002B are linked together and have been provided
with four supplies, two of which are interlocked. The switchboard sections have different ratings.
It is not clear what the intention is with this arrangement. Drawing Error.
viii. A number of checks on the size of containment leaving the substations has been carried out,
the checks would indicate that the containment is under sized in some locations. All containment
sizes should be reviewed by the designers. Refer to attached DSSR calculation sheets for sub-
station LGN, 03SA and 03SB
3.2 Earthing and Bonding
From our review of the scheme with Arup the works they described for all aspects of the earthing and
bonding indicates that it is the intension of the design to comply with all HTM and wiring regulation
requirements.
From the documents available to us we would however offer the following comments and
observations.
3.2.1 MV Earthing
The Contract issue documents available to us does not include an earthing schematic for the MV
earthing design
This information needs to be provided to allow us to review and comment on the design.
3.2.2 LV Earthing
From the documents available to us we would however offer the following comments and
observations.
i. It is noted that the neutral earth connection at each substation is located in the main LV
switchboard. With this arrangement when a transformer is taken out of service, and the sister
transformer is required to support the load of both substations, there are two neutral earth
connections in circuit. This can lead to circulating neutral currents. To be reviewed by the
designers.
We would expect the neutral earth connection to be on the live side of the transformer ACB,
and 4 pole ACB’s provided at each transformer and bus section ACB’s. With this arrangement
only one neutral earth connection is in circuit when operating on one transformer. To be
reviewed by designer.
ii. What are the MV earthing arrangements at each substation. The earth connections to the MV
switchgear/cables is not indicated.
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iii. The size of earth conductors appears excessive, can earth fault calculations be provided to
demonstrate the sizes indicated. The earth fault calculation assumes an earth fault level of
65kVA, this appears high. The actual earth fault level should be established.
iv. The earthing schematic provides general design principles, but does not detail the actual
connections required at each location, for example the bonds to incoming services, structure,
or the lightning protection system are not detailed. Is it intended to create an equipotential zone
at each distribution centre? The designers to develop the earthing strategy with the Contractor.
v. Any specific earthing requirements for the data network or equipment rooms has not been
detailed. This is indicated on the general earthing schematic but the use of parallel earth cables
can create interference. Designers to review and consider single earth connection.
3.2.3 Generators
The current design has all generator transformers connected to earth via a single panel marshalling
each generator to a single neutral earth resistor. This is a single point of failure and as these resistors
need regular cleaning all generators would be unavailable during a fault or maintenance condition.
We would recommend that the arrangement be reconfigured to at least two panels and resistors to
bring the risk to the Hospital down to a manageable level. This recommendation has been
incorporated into the design.
The size of the neutral earth resistor has not been provided, this will need to be defined to allow
protection grading of the network when operating in island mode. A grading study should be provided
indicating the protection arrangements when operating it island mode. Resistor size to be reviewed
by the designers in conjunction with the generator vendor and the requirements of the electrical
protection grading study.
3.2.4 Patients and Medical Equipment
The earthing of these key risk areas is controlled by the use of Isolated Power Supplies (IPS) and the
use of local earth bars adjacent to Group 2 medical areas. From the review of the Group 2 medical
locations earthing schematic we would offer the following observations.
i. An antistatic floor is indicated, this provision is unusual and if not provided should not be
indicated on the schematic.
ii. The earthing arrangements are not in accordance with the recommendations of BS7671.
iii. Earthing arrangements of Group 1 medical locations has not been provided for review. Note
that under the current edition (18th) of BS7671 Group 1 supplementary equipotential bonding
has to achieve 0.2 ohms as Group 2 locations.
iv. The Theatre Layout earthing drawing indicates that additional earth reference bars maybe
installed above ceilings, this would not be compliant with BS7671.
3.3 Fire
3.3.1 Fire Strategy
i. The fire strategy has been defined by a specialist Fire Engineer and the MEP design proposals
have been developed by Arup to reflect that strategy.
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ii. It should be noted that the fire strategy has been fundamentally changed by the introduction of
sprinklers to all areas of the hospital, including ceiling voids, whereas initially it is understood
that it was intended to apply sprinklers only to high risk areas.
iii. Following the introduction of sprinklers to all areas there is an opportunity to modify some other
fire protection measures such as ceiling void detection, reduction of hazard rooms and escape
requirements. These opportunities have not yet been developed resulting in the retention of
elements which may not be required.
iv. It is noted that fire suppression using gaseous systems is included to a number of areas
including generator transformer rooms, main switch rooms, main equipment rooms and medical
records. This is not unexpected with the internal location of much of the plant. It is unusual
however to include fire suppression to electrical switch-rooms but this has been identified as a
requirement of the fire authorities.
Provision of gaseous fire suppression systems is expensive and requires regular maintenance.
v. Resolution of the base fire strategy is to be completed by the Fire Specialist to enable Arup to
complete the M&E design on the correct basis.
3.3.2 Fire Detection and Alarms
The fire alarm system is a fully addressable system designed for life safety and includes for detection
in all ceiling voids.
Our review to date has not identified any problems with the design other than the potential to reduce
void detection following a review by the Fire Engineers.
3.3.3 Evacuation Strategy
Arup advise that to date that no formal evacuation strategy has been produced by the Hospital but
they have based the fire systems on the following basis:
i. The basis of the fire strategy is of progressive horizontal evacuation as defined in HTM 05.
ii. Due to the height of the building fire evacuation lifts are included.
The evacuation does need to be formalised as address all areas such as isolation rooms to ensure
that the engineering services and the evacuation procedures are complimenting each other.
3.3.4 Fire Alarm Cause & Effect
The fire alarm cause and effect documentation has yet to be produced by Arup and this is a critical
element of the design that needs to be completed. The reasons for the delay to this is that the
programming and configuration of the fire alarm activation needs to reflect how the Hospital wish to
evacuate the various building occupants and that strategy is not yet available.
This is a very important piece of work that needs to be progressed in a timely manner.
3.3.5 Smoke Damper Switching Strategy
The strategy for the closing of smoke dampers in a fire condition is closely allied to the fire alarm
cause and effect documentation that has yet to be produced by Arup. This is a critical element of the
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design that needs to be completed. The reasons for the delay is the same as for the fire alarm cause
& effect.
This is a very important piece of work that needs to be progressed in a timely manner.
3.3.6 Smoke Ventilation
i. It is noted that smoke ventilation systems are provided to the basement, atrium areas and fire
escape stairs. The ductwork rises through the building via fire rated ductwork.
ii. It is understood that smoke ventilation to the car park is included but not used in the event of a
fire as sprinklers are included, and it is preferred to contain the fire locally and allow the
sprinklers to extinguish the fire before it spreads. The smoke clearance system can then be
manually operated to clear smoke following the fire.
3.3.7 Fire Rated Ductwork / Fan Systems
i. Fire rated ductwork is defined on the ventilation drawings and specified in the Equipment Data
Sheets. The ductwork is specified to have a 2 hour fire resistance for stability, integrity and
insulation as would be expected. The detail of the construction appears to be left to the installer
and it must be ensured that a certified proprietary system of ductwork and supports is installed.
ii. The provision of access doors in fire rated ductwork, particularly to kitchen extract systems, will
be required. It must be noted that HTM 03 refers to fire rated ductwork (cl 5.19) and states that
the fire rated section of ductwork must not be penetrated by test holes or access hatches. Whilst
this is a very specific situation this clause is interpreted by some to exclude the provision of
access hatches. A derogation is perhaps prudent.
Arup have agreed to review a derogation with NPHDB in particular for kitchen extract ductwork.
It is important that any fire rated ductwork provision and specification is agreed with Fire Officer,
Fire Engineer and Building Inspector to ensure compliance and also ensure that the provision
is fully documented in the Fire Strategy at completion.
iii. Extract ductwork to “Iso” rooms is shown as lead lined. It is not clear that this ductwork is fire
rated but fire dampers are understandably not installed.
Arup have confirmed that fire rated ductwork is included as well as lead lining to these specialist
rooms.
4 DEROGATIONS REGISTER
The derogations register has been received for review and the following comments should be
considered;
i. Item 1 – Humidification is only proposed for limited areas including burns unit, MRI rooms,
orthopaedic theatres and cardiac theatres. Agreed by NPHDB
Other areas should also be considered to require humidification including; MRI technical rooms,
other imaging/scanner rooms, pharmacy and critical care spaces.
HBN 06 Imaging requires humidity control to virtually all examination rooms and refers also to
manufacturers recommendations.
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ii. Item 3 – HTM 06-01 – The installation described in the derogation does not appear to be
reflected on the LV schematic drawings. The sub main circuits from the UPS equipment is not
fire rated.
iii. Item 3 – HTM 03 - Heater batteries may be located above rooms served – agreed by NPHDB
Where there is no practical option this has been applied but a catch tray and leak detection
included. The provision of a catch tray may add to the inspection, cleaning and maintenance
access required within a patient area and should be reconsidered.
The provision of drains to heater battery catch trays is not clear on the drawings and
specification.
Arup have confirmed that heater battery catch trays are currently provided with drains however
have recommended the drains be removed to realise a cost saving. Arup have suggested that
NPHDB instruct removal of drains from re-heat coil catch trays, however whilst the omission
needs to be accepted by NPHDB this is really a design issue. Drains to catch trays would be
considered a risk as it is likely that the trap will dry out leaving a potentially unsealed connection
to a drain within a clinical space.
iv. Item 4 – HTM 03 - Fan coils are located in ceiling voids above areas served – agreed by NPHDB.
Whilst this is a commonly applied approach location above patient areas should be avoided as
regular maintenance will be required. A catch tray as applied to reheat batteries is impractical
however the risk is the same.
v. Item 5 - HTM 03 – Cooling coils will be located above the area being served - agreed by NPHDB
Cooling coils located in ceiling voids, particularly above patient areas, should be avoided as
regular inspection, cleaning and maintenance is required to avoid bacteriological risk.
The provision of secondary catch trays, as for heater batteries, should be confirmed.
Whilst the derogation has been included none have been noted in the review. Arup have
confirmed that there are no local cooler batteries in the present design.
Where cooling coils may be included in ceiling voids the method of construction of the duct
section, including drain tray and discharge connection should be agreed with AE and
maintenance engineers. Easy and safe access must be provided to enable inspection and
cleaning.
vi. Item 6 – HTM 03 – Provision of a shared air handling unit for two operating theatres – not agreed
by NPHDB as a single plant per theatre is included at present.
Whilst the provision of shared air handling plant between two theatres is contrary to HTM 03 as
flexibility in operation and maintenance is compromised this can be successfully applied if
accepted by the client and maintenance team.
It should be noted that the CHG Brief excludes this strategy by reference to minimising down
time.
vii. Item 8 – HTM 04 – Bypass around water meters excluded – agreed by NPHDB.
Whilst the omission of the bypass and avoidance of a dead leg to flow is reasonable an
unmetered connection to the hydrant supply should be provided. Arup have committed to review
with OCSC.
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viii. Item 10 – HSE guidance – HES guidance recommends that healthcare records management is
maintained at a temperature as close as possible to 180C – this has been revised to 210C and
agreed by NPHDB.
The reason for the close temperature control is not clear and 180C is too cold for regular
occupancy. The 210C agreed is still low for airconditioned spaces and should be reconsidered.
Arup have confirmed that 21oC is selected as the heating temperature with cooling to satisfy the
requirements for occupancy typically 230C.
ix. Item 11 – HTM 06 – the location of IPS units in the theatre plantroom is proposed and whilst
this is often accepted this is a compromise on the ideal location on the same floor and close to
the area served. Earth resistances must still be maintained regardless of location. Also as the
installation is considered as a “safety Circuit” within BS7671 adequate fire protection must be
provided.
x. Item 12 – HTM 03 – The achievement of 6 air changes/hour in ward bedrooms. This should not
be applied to naturally ventilated rooms however the mixed mode system proposed does
achieve this criterion so no derogation is required.
The ward ventilation strategy is however complex, expensive and difficult to control and should
be reviewed as noted elsewhere in this report. A derogation may then be required.
Ward bedroom ventilation has been reviewed as potential VE item. The aim of the system is to
provide a level of permanent ventilation within a naturally ventilated area, and will achieve the
6 air changes/hour. If the strategy is modified the need for a derogation should be reconsidered.
xi. Item 14 – HTM 06 – The start-up of emergency standby generators within 15 seconds will not
be achieved – agreed by NPHDB.
The requirement of HTM 06 is that power is reinstated to critical areas within 15 seconds which
requires generators, possibly multiple machines, to start up and take on load within 15 seconds.
The start-up and loading strategy should be analysed to ensure that all critical areas are
reinstated in the specified time. If this cannot be achieved battery autonomy will need to be
increased from 1 hour to 3 hours at considerable capital and battery replacement cost.
The agreed derogation refers to the supply being on line within 320 – 30 seconds, it is assumed
that this should read 20 – 30 seconds?
xii. Item 16 – HTM 03 – The provision of one AGSS system per theatre required by HTM 03 is
relaxed to shared systems – agreed by NPHDB
The provision of a single AGSS pump to each theatre is recommended in HTM 03 to maintain
flexibility in maintenance operations. A spar pump should be held on site for use in the event of
a failure. Arup have confirmed that the spare pump is included in the specification.
Provision of duplex pump units serving multiple theatres is reasonable although more difficult
to manage in a maintenance situation. AGSS systems should not include too many outlets or
they become difficult to balance. Three to four theatres per system is not considered
unreasonable.
xiii. Item 17 – HTM 04 – The provision of 12 hours water storage in lieu of 24 hours is proposed –
rejected by NPHDB
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The provision of excessive storage is not recommended by HTM 04, ref clause 8.5, and does
recommend a reduced storage of 12 hours. It is recognised that accurate assessment of daily
water use is difficult to define and suggests a realistic assessment is made based on the best
information available. Historic figures of 900 L/bed/day are considered excessive.
This issue should be revisited and a derogation from HTM 04 should not be required as the 12
hours is stated in the HTM. A derogation may however be required relating to Dublin City or
HSE requirements.
5 OTHER MATTERS
5.1 Supporting Infrastructure between M&E Systems
5.1.1 Mechanical Plant and BMS Power Supplies
Power supplies to the mechanical plant and BMS are all provided via the resilient A & B distribution
network so are as secure as all the hospital power supplies.
All BMS points associated with a system are wired to a common outstation so control of a particular
system does not require use of the IT network. This improves the resilience of the control and reduces
traffic on the network.
5.1.2 Cooling of Electrical Equipment Rooms
As many of the electrical sub stations, UPS room etc generate significant amounts of heat they require
this heat to be dissipated from the building. For the internal spaces Arup have chosen to use
mechanical cooling utilising the chilled water system.
The design provides redundancy with respect to major components they are all served by a common
pipework system which a potential single point of failure. Whilst this is not a significant risk above
other forms of mechanical cooling this needs to be considered when carrying out maintenance or in
abnormal conditions such as loss of mains electricity, generator failure etc.
Arup have commented that there are multiple pumped circuits, with the header as the only potential
single point of failure and that this risk will require a management strategy. Whilst the risk will need to
be managed during the operation of the building the risk remains in some circumstances which should
be considered in planning for such eventualities.
Arup have also confirmed that duty/standby chilled water cooling units have been provided to give
resilient cooling to the electrical plant rooms.
DSSR suggested to consider changing the standby units to DX and whilst Arup agree this would
further increase resilience it must be noted that it would incur significant additional costs.
Alternatively, Arup suggest CHG could develop an emergency management strategy to provide
cooling in the unlikely event of a total loss of the CHW system e.g. portable cooling units / fans could
be deployed in an emergency scenario. This is not considered practical unless as a last resort and
the risk from loss of cooling to electrical rooms must be recognised in the operational manuals and
contingency planning recognised by the FM team.
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5.1.3 Load Restoration / Generator Load Shedding
Following a mains failure and the generators starting there is a need to restore the building electrical
load in a controlled and pre planned manner. In our discussions with Arup it was recognised that this
had to be done but how this was to be achieved and what the agreed sequence was had not yet been
designed.
This needs to be resolved as the cooling system (see above) is critical to the operation of the electrical
systems and the IT so needs to be quickly restored along with critical medical areas.
There is also a need to consider the eventuality of a number of the generators either not starting or
becoming un available. This will require loads to be turned off and again this needs to be an agreed
priority order and normally needs to be done via the BMS rather than at substation level. In our
discussions with Arup it was recognised that this had to be done but how this was to be achieved and
what the agreed sequence was had not yet been designed.
5.1.4 Plant Replacement Strategy
Whilst we have not had sight of a formal Plant Replacement Strategy document our meeting with Arup
and review of the available design information has highlighted the following points
i. Chillers
The chillers are mounted at roof level above the ward accommodation. The future replacement
has been considered by utilising the lifts for key component replacement and the cranage of
replacement chillers has been reviewed and cranage plans generated by the Design Team. The
cranage plans that we were shown to us by Arup need to be part of a formal document for
review prior to the project design being completed.
ii. Transformers and Switchboards
Transformers and Switchboards at roof level to serve the mechanical plant will be maintained
and replaced as described for the chillers.
All other sub stations are internal and the replacement of transformers and switchboards will
require the use of corridors and lifts and Arup advise that transformer casings will have to be
removed to achieve this. This is clearly far from ideal and so the route of all components need
to be recorded and factors such as floor finishes etc reviewed prior to the design being
completed.
iii. Generators
From our review of the documentation and discussions with Arup we are concerned that the
space available to install, maintain and replace the emergency generators has a significant
impact on the operation and maintenance of the Hospital. Our main concerns are as follows:
• Generators 1 and 2 (nearest the switch room) do not appear to be able to be installed as
complete units with all walls constructed. Arup advised that FG Wilson; the proposed
supplier has reviewed the arrangement and we would welcome sight of their proposed
method statement and tracking analysis.
• The arrangement for the removal of Generator 5 will not work once Generator 6 is
installed so this area needs to be revisited.
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• The space shown between the pairs of transformers for access and replacement of major
components e.g. engines and alternators need to be reviewed and confirmed it is
adequate for safe access.
• The risk assessment and method statements for maintaining each set needs to be
reviewed as if both sets within a “cell” have to be made unavailable during any
maintenance the Hospital will be operating on N–1 generators so load management may
need to be anticipated and planned for.
• If in order to replace a single generator there is a need to remove both step up
transformers from the generator cell then a temporary generator will be required to
provide the Hospital with N generators. Provision is made on one of the generator
switchboards but a location and temporary cabling route needs to be established now as
part of the design philosophy.
The key to resolving these questions is the detailed proposals by the Contractor for the
installation, maintenance and removal of the generators.
iv. Boilers and CHP
From our review of the documentation and discussions with Arup we are concerned that the
space available to install, maintain and replace both the LTHW and Steam boilers and the CHP
could have a significant impact on the operation and maintenance of the Hospital. Our main
concerns are as follows:
• All ancillary equipment is not shown on the Arup design drawings and once this is installed
the available space for removing and replacing boilers will be compromised.
• Arup advise that the Contractor is proposing to change the plant room access and egress
points for the boilers. Whilst this may improve matters we have not had sight of the
proposed changes or whether plant layout changes are also proposed.
Arup are aware of this issue but it must be managed to an acceptable conclusion that allows
the Hospital to operate reliably even during plant replacement. Access for boiler and CHP plant
has been reviewed with tracking plots by the installers and there is general consensus that
equipment can be installed and replaced.
The initial plant replacement strategy has been confirmed by Arup but the final document will
be developed by the contractor. Reviews of access for installation and future replacement ate
being carried out by the installers as part of co-ordination activities. This exercise remains
ongoing.
5.2 Spatial Coordination Capacity in Primary distribution
Services within corridors will inevitably be congested as main service routes will always run along
corridors where possible to avoid unnecessary access into occupied areas, particularly in specialist
clinical rooms such as imaging theatres etc.
The design drawings show multiple services in corridor ceiling voids and whilst the drawings are
produced in 3D it is noted that the final coordination is to be completed by the contractors.
It is not clear who is intended to take the lead in the final coordination exercise given that there are
multiple services contractors all producing installation drawings/models coordinating pipework,
ductwork, medical gases, drainage pipework, electrical containment, data services, sprinklers and
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other specialist services. Several of the services installations are subject to contractor design and as
such information may not yet be available for coordination.
Examination of the design drawings shows the extent of services to be accommodated and indicates
that some problems should be anticipated. Main service routes show large electrical tray and trunking
which will need to be at low level within the void with other services routed at higher levels. Where
cable trays are widest near switch rooms, hub rooms and distribution cupboards access will be very
restricted.
Initial assessment shows that cable trays may be undersized particularly around main equipment
rooms and hub rooms where large numbers of data cable will be grouped, and around main switch
rooms where sub mains cables are large and inflexible. The extensive data network envisaged for the
development will add to the congestion around data rooms. We have not seen the level of detail to
determine how many cables will follow each route but a review by the designers and contractors
should be completed.
It must also be noted that the ductwork specification requires access doors at regular intervals or
cleaning. These access doors are not shown on the ductwork drawings so when positioned other
services may require adjustment to achieve safe and workable access. Arup have confirmed that the
position of ductwork access doors is part of contractor co-ordination all of which is being reviewed as
the design progresses. Adequate access for maintenance functions should be verified during
commissioning and testing activities.
Plantroom drawings include cross sections taken from the 3D model. These show the basement
plantrooms to be very tight with the top of plant close to the soffit. Air handling units are drawn as a
shallow profile which increases the width. As well as being as high as can be fitted the width may
cause difficulties in cleaning and maintenance operations. It is assumed that manufacturers
dimensions have been used as the basis of the model giving confidence that units will not grow in
physical size but this should be verified.
Some air handling plant is shown with columns in the access zone. Whilst the columns may not inhibit
coil withdrawal overall access may be restricted and care will need to be taken in the accurate
positioning of plant to maintain all necessary access.
Arup have confirmed that the latest coordination models are including final equipment selections and
space provision is shown to be improving. Spatial fit is being reviewed and agreed in weekly co-
ordination meetings.
The air handling unit manufacturers should be asked to demonstrate that access is practical with the
unit profiles as proposed.
It does not appear that any significant spare space has been included within plantrooms, risers or
ceiling voids for the addition of future systems.
Specific space has been allocated for known future addition of major plant, such as boiler, generator,
chiller and oil storage. All other future expansion is defined as the meadow site where additional
buildings will be located. Primary service distribution the future development is stated to be via the car
park, resulting in the loss of some parking spaces.
A considerable amount of ductwork is routed over rooms and whist this is not unusual for heavily
serviced hospitals it can result in increased costs due to the potential number of walls, including fire
and acoustically treated walls penetrated.
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Due to congestion in corridors a number of fan coils units, reheat batteries and volume control
dampers are located above occupied areas. Reference is included to cooling coils located in ceiling
voids but none have been noted. Access to all such equipment will cause potential nuisance and
disrupt the operation of the hospital. For example, volume control dampers are shown above the MR
examination room ceiling which will be inaccessible due to the RF cage.
Arup have commented that generally VCDs are fixed at commissioning and those above MRI room
will be relocated. Whilst it is unlikely that volume control dampers will be adjusted regularly they will
need to be accessible in case of modifications to ductwork requiring any rebalancing of the systems.
The client brief refers to future flexibility but this is limited to modifications with spaces such as
theatres, scanner rooms etc. where a change of equipment specification or clinical activity is
anticipated. There appears to be no defined requirement for spare capacity in plantrooms, risers or
ceiling voids.
Arup have confirmed that spare capacity for all systems is set out in relevant reports and that there is
no brief or budget for spare capacity in plantrooms, risers or ceiling voids. This is a short-sighted
approach which will inevitably result in problems in the future where minor modifications may be
requested which may then not be possible.
5.3 Robustness of Performance requirements for Contractor Designed Elements
The specialist sub-contractors detailed design proposals have not been received for review and it is
not known if these are available. It is assumed that the design proposals will be reviewed in detail by
Arup with respect to compliance with the performance criteria and coordination with other design
specialists but if concerns remain further a review can be carried into specific systems.
The main system of possible concern would be the steam and condensate design as there is potential
for interpretation of what is acceptable and this is a spatially challenging system requiring considerable
maintenance access.
5.4 Future Flexibility
i. The overall building and engineering design proposals allow for 20% future expansion, as
required by the brief. This is identified as expansion space on the “meadow garden” at the North
of the site.
ii. It is intended that the expansion space is serviced as follows;
• Space has been allowed for an additional heating boiler.
• Space has been allowed for a 6th emergency stand-by generator
• Dedicated ventilation plant will be installed on the roof of the future expansion space.
• Dedicated chiller plant will be included within the expanded space.
• Provision of medical gases has not been clarified but it is assumed that oxygen will be
derived from the site network but other gases will likely be provided locally.
iii. The 20% expansion has not been allowed on each engineering system.
iv. The Maternity building will, like the expansion space, be services from the additional heating
boiler and will also be provided with dedicated ventilation and chilled water plant.
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v. Electrical supplies to the Children’s Hospital, Maternity Hospital and St James Hospital will all
be connected to dedicated incoming supplies as ESB regulations forbid selling power to
secondary users. As a result, the whole site requires the provision of 3 independent power
supplies at significant additional cost to the potential to share the supply.
It is understood that this has been challenged and the provision of a primary substation
proposed on the site. This however has not been accepted, but should be pursued if still
possible.
Offices at: Glasgow Harrogate London Manchester T 0141 334 6161 T 01423 520252 T 020 8567 5621 T 0161 872 4811 F 0141 357 1993 F 01423 520325 F 020 8579 5649 F 0161 872 7325 E [email protected] E [email protected] E [email protected] E [email protected]