Manual Stack-Emission MonitoringPerformance Standard for Organisations

Environment Agency September 2003

Version 4

Record of amendments

Versionnumber

Date Section Amendment

2 August 2002 Annex C Updated contents of Annex.3 October 2002 4.4.2 Deleted requirement for site-specific protocol to be

signed by process operator and competent authoritybefore carrying out monitoring.

3 October 2002 5.4.1 Approval should be sought from the competent authorityif an organisation modifies a technical procedure to takeinto account site-specific conditions. It is not essential forthe monitoring organisation to have obtained approvalbefore carrying out the monitoring.

3 October 2002 5.4.2 Amended hierarchy of methods and added informativenote

4 September 2003 Annex H Amended Annex H : Stack emission monitoring report

Foreword

The Environment Agency established its Monitoring Certification Scheme: MCERTS todeliver quality environmental measurements. The scheme provides for the productcertification of instruments, the competency certification of personnel and the accreditation oforganisations based on international standards. The term ‘organisation’ is used generically. Itincludes commercial ‘test houses’, laboratories, and industrial operators’ in-house monitoringarrangements. MCERTS is progressively being extended to cover all regulatory monitoringactivities.

MCERTS for manual stack-emission monitoring has been developed in collaboration with theSource Testing Association (STA), the UK trade association representing manual emissionmonitoring companies, the Scottish Environment Protection Agency (SEPA) and theEnvironment and Heritage Service, Department of Environment, Northern Ireland.

The scheme is split into two components – the certification of personnel and the accreditationof organisations. This document provides the performance standard for organisations.

MCERTS requires stack-emission monitoring organisations to be accredited by the UnitedKingdom Accreditation Service (UKAS) to ISO/IEC17025 for the MCERTS standard. Itprovides an application of EN ISO/IEC 17025 in the specific field of measurement of airemissions from stacks and covers:

• ethical requirements for independence and environmental awareness;• use of MCERTS certified personnel;• selection of appropriate methods following international standards;• method implementation;• estimation of measurement uncertainty;• use of appropriate equipment;• planning of a sampling measurement campaign

- site review- risk assessment- site-specific protocol;

• reporting of results;• participation in proficiency-testing schemes.

The standard does not provide a sectorial application for analytical laboratory methods butdoes specify that any methods shall be accredited to the requirements of EN ISO/IEC 17025.

The MCERTS personnel competency standard is published as a separate but related MCERTSdocument. It defines the standards for certifying stack-emission monitoring personnel ascompetent based on experience, training and examination. Sira Certification Service (SCS)operates the personnel competency scheme on behalf of the Agency and is accredited byUKAS to European Standard EN45013: General Criteria for Certification Bodies OperatingCertification of Personnel.

The benefits of MCERTS for stack-emission monitoring are that it:

• provides formal certification of personnel and accreditation of organisations in accordancewith European and international standards;

• provides assurance to all stakeholders, including industrial process operators, stack-emission monitoring personnel and organisations, regulators and the public, of thereliability of stack-emission monitoring data;

• establishes a level playing field in the competitive stack-emission monitoring marketbased on the Agency’s requirements;

• sends a message that manual stack-emission monitoring is a critical component inproducing defensible data for regulatory purposes;

• promotes and raises the professional standing of stack-emission monitoring personnel andorganisations by establishing 'quality standards' to which all should aspire and by whichall shall be judged.

If you have any questions regarding the accreditation process, or would like furtherinformation on how to apply, please contact:

UKAS21 – 47 High StreetFelthamMiddlesexTW13 4UN

Tel: 020 8917 8400Fax: 020 8917 8500Email: info@ukas.com

Further information on MCERTS, including copies of the performance standards,examination syllabuses and guidance, can be obtained from the Agency’s website at:

www.environment-agency.gov.uk/business/mcerts/

If you have any general questions about MCERTS, please contact:

Environment Agency Tel: 01772 714362National Compliance Assessment Service Fax: 01772 714360Lutra HouseDodd Way, off Seedlee RoadWalton SummitBamber BridgePreston PR5 8BX

Stuart NewsteadHead: National Compliance Assessment ServiceFebruary 2002

Contents

Introduction 1

1. Scope 2

2. References 3

3. Terms and definitions 3

4. Management requirements 5

5. Technical requirements 7

5.1 General 7

5.2 Personnel 7

5.3 Accommodation and environmental conditions 7

5.4 Test methods and method validation 8

5.5 Equipment 10

5.6 Measurement traceability 12

5.7 Sampling 12

5.8 Handling of test items 14

5.9 Assuring the quality of test results 14

5.10 Reporting the results 15

6. Status of this document 16

Annex A - Environmental policy 17

Annex B - Health and safety 18

Annex C - Equipment calibration 21

Annex D - Site review 22

Annex E – Site-specific protocol 23

Annex F - Work file 25

Annex G - Monitoring records 26

Annex H – Stack-emission monitoring report 27

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MCERTS performance standard for organisations carrying out manualstack-emission monitoring

Introduction

Manual stack-emission monitoring for regulatory purposes includes measurements for:

• determining compliance with numerical limits in authorisations and permits;• the calibration of continuous emission monitoring systems (CEMs);• acceptance trials on new pollution abatement plant or alternative fuel

applications.

Note - stack-emission monitoring is a general term used to describe the preparation work prior to a measurementcampaign, undertaking the site work, calculating the monitoring results and producing the final report for theclient.

The extension of MCERTS to include manual stack-emission monitoring is built on proveninternational standards to ensure good quality monitoring data. The scheme is split into twocomponents – the certification of personnel to the MCERTS personnel competency standardand the accreditation of stack-emission monitoring organisations to the MCERTSperformance standard for organisations.

The general requirements for the competence of testing laboratories are described in theInternational Standard EN ISO/IEC 17025. This contains all the requirements laboratorieshave to meet if they wish to demonstrate that they operate a quality system, are technicallycompetent, and are able to generate technically valid results.

Note - laboratories are referred to as stack-emission monitoring organisations (organisations) throughout thisperformance standard. This covers both independent monitoring organisations and those which have in-housemonitoring teams.

EN ISO/IEC 17025 recognises at para.1.6 Note 1 that it might be necessary to explain orinterpret certain requirements in this International Standard to ensure that the requirements areapplied consistently.

This MCERTS performance standard provides criteria for the application of EN ISO/IEC17025 in the specific field of monitoring of emissions from stationary sources (for example,chimney stacks). In producing this MCERTS standard, the guidance for establishingapplications for specific fields given in Annex B of EN ISO/IEC 17025 has been followed.

This standard does not re-state all the provisions of EN ISO/IEC 17025. Monitoringorganisations are reminded of the need to comply with all the relevant criteria detailed in ENISO/IEC 17025.

The clause numbers in this document follow those of EN ISO/IEC 17025, although the textfrom this International Standard is not repeated. Where no additional requirements areneeded, this is stated.

This standard should be used in conjunction with its companion standard the MCERTSpersonnel competency standard. This is available on the Agency’s web-site at: www.environment-agency.gov.uk/business/mcerts/.

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1 Scope

1.1 The monitoring of stack-emissions is often called measurement, testing or sampling.In this document, the term monitoring is used except where the specific meanings ofthe alternatives are more appropriate.

The manual monitoring of stack-emissions can involve taking samples for laboratoryanalysis, the in-situ determination of flue gas physical parameters such as temperature,pressure and flow rate, and of particulate loadings by isokinetic sampling, and the in-situ periodic instrumental monitoring of pollutants. This form of monitoring stack-emissions is widely used, particularly where continuous emission monitoringinstruments are not available or are judged to be inappropriate for reasons of cost ortechnical application. Its primary use is for regulatory purposes, includingmeasurement for determining compliance with authorised numerical limits, calibratingcontinuous emission monitoring systems and acceptance trials on new pollutionabatement plant.

The monitoring of emissions from stationary sources can be undertaken for a widerange of substances using various standard methods. Details of standard methods areprovided in the Agency’s Technical Guidance Note M2. The methods organisationsare accredited to monitor under EN ISO/IEC 17025 for the MCERTS performancestandard shall be defined in their scope of activities.

1.2 This document is applicable to all organisations performing monitoring of emissionsfrom stationary sources.

1.3 No additional requirements to EN ISO/IEC 17025.

1.4 Accreditation of organisations to this performance standard will demonstrate that theymeet the UK environment agencies’ MCERTS requirements for regulatory monitoringof stack-emissions from stationary sources.

1.5 The MCERTS standard contains both technical and health and safety requirements.Compliance with regulatory and safety requirements on the operation of laboratories isnot covered by EN ISO/IEC 17025. However, carrying out stack-emission monitoringis hazardous (for example, working at heights, lifting equipment, exposure tochemicals); and, if correct health and safety practices are not adhered to, the quality ofthe monitoring is often compromised.

Note - The health and safety requirements are set out to ensure that organisations have a health andsafety management system and are following safe systems of work (for example, undertaking riskassessments). UKAS will audit whether these systems are in place – it is not auditing the adequacy ofthe systems. However, if UKAS assessors observe poor health and safety practice they will inform theAgency. The Agency will then inform the relevant site inspector and the local health and safety office.

1.6 No additional requirements to EN ISO/IEC 17025.

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2. References

BS EN ISO 14956/2001 Evaluation of the suitability of a measurement method by comparisonwith a stated measurement uncertainty.

EN 45013 European Standard for bodies operating certification of personnel.

Hazards, Risk and Risk Control in Stack Testing Operations, Source Testing Associationdocument HS1069-00 (updated frequently).

EN ISO/IEC 17025:2000 General requirements for the competence of testing and calibrationlaboratories.

MCERTS Personnel Competency Standard, Environment Agency, 2002.

Technical Guidance Note M1, Sampling Requirements for Monitoring Stack-Emissions to Airfrom Industrial Installations, Environment Agency, 2002.

Technical Guidance Note M2, Monitoring of Stack-Emissions to Air, Environment Agency,2002.

3. Terms and definitions

Competent authority – organisation responsible for implementing environmental legislation(for example, in England and Wales the Environment Agency, in Scotland the ScottishEnvironment Protection Agency (SEPA) and in Northern Ireland the Environment andHeritage Service).

Conformance testing – measurements and evaluations carried out on an instrument and/orequipment to determine its compliance with a specified performance standard or requirements(for example, in MCERTS product certification).

Emission-limit value – the numerical limit on an emission (for example, mass, concentration),that may not be exceeded during one or more periods of time. Emission-limit values may alsobe laid down for certain groups, families or categories of substances.

Isokinetic sampling – sampling at a flow rate such that the velocity and direction of the gasentering the sampling nozzle are the same as the gas in the duct at the sampling point.

Measurement campaign – the scope of work required on a particular site for a specific timeperiod.

Measurement series – successive determinations carried out at the same sampling plane, andat the same process conditions.

Method Implementation Document – document published by the Agency outlining it’sinterpretation of the standard method.

Overall field blank – a measurement sample taken at the plant site in an identical manner tothe normal samples in the series, except that no gas is sampled.

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Risk assessment – an assessment of the health and safety hazards and associated risksinvolved in stack measurement at a specific work location.

Sampling equipment – equipment used to take samples of stack-emissions, instruments usedfor direct reading of stack-emissions and instruments used to gather supporting informationon environmental conditions pertaining at the time of the measurements.

Sampling plane or sampling section – a plane normal to the centreline of the stack at thesampling position.

Sampling point – specific position on the sample plane where the sample is extracted.

Sampling port – holes in the wall of the stack through which access to the exhaust gas can begained.

Sampling position – a suitable position on the plant where representative samples can beobtained.

Site specific protocol - the installation specific application of an organisation’s technicalprocedures. A protocol describes how the measurement method shall be employed in a givensituation. This may also be referred to as the measurement plan.

Site review – a visit conducted by the organisation before undertaking stack-emissionmeasurements to ensure the physical and logistical situation is fully understood beforearriving on-site to conduct work. The review, sometimes referred to as a reconnaissance visit,provides essential information for determining the appropriate measurement method and sitespecific protocol and for carrying out a risk assessment.

Stack - structure through which pollutants are released to atmosphere. Chimney stacks areintended to be of sufficient height to adequately disperse emissions in the atmosphere.Measurement of emissions may also be undertaken in ducts, flues and vents.

Stack-emission monitoring organisations – organisations that undertake the measurement ofemissions to air from stationary sources. This can include work undertaken at the laboratory’spermanent facilities, at sites away from their permanent facilities and in temporary or mobilelaboratories.

Standard conditions – gas pressure, temperature constants and moisture conditions to whichmeasurements are referenced (101.3kPa; 273K; dry gas). Gases may also be referenced tostandard conditions of oxygen.

Stationary sources – fixed position industrial processes from which emissions to air via stacksare made.

Technical procedure – the organisation’s detailed written procedures on how to perform amethod in line with its quality system.

Testing – is used in EN ISO/IEC 17025 to describe the routine methodical assessment of anentity. Testing may include sampling, measurement and monitoring. In this document the

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term monitoring is used except where the alternative is more appropriate. Also seeConformance testing.

UKAS – the United Kingdom Accreditation Service, the body appointed by the Governmentto assess and accredit organisations that provide testing services to international standards, forexample EN ISO/IEC 17025.

Work file – a file in which details of the stack measurement campaign for an individual siteare recorded.

4 Management requirements

4.1 Organisation

4.1.1 – 4.1.2 No additional requirements to EN ISO/IEC17025.

4.1.3 The management system shall stipulate that analysis of substances in a laboratory shallbe undertaken by a laboratory that holds accreditation to EN ISO/IEC 17025 for therelevant method.

4.1.4 Stack-emission monitoring shall be carried out by an organisation that is free from anycommercial, financial and other pressures that might influence their technicaljudgement. Industrial process operators using in-house monitoring teams shall havemanagement structures that ensure this requirement is met.

The results of all monitoring carried out for regulatory requirements shall be reportedby the monitoring organisations to their customers (that is, to industrial processoperators or the competent authority). This requirement includes results showing non-compliance as well as compliance with emission-limit values.

Authorisation for any departures from an organisation’s documented policies andprocedures shall be obtained from the competent authority.

An organisation shall have an environmental policy in place and take managementaction to minimise the environmental impact of its operations.

Note – Annex A provides details of good practice.

An organisation shall implement a health and safety policy addressing the hazards andassociated risks to health and safety in the activities associated with stack-emissionsmonitoring. Organisations shall meet the requirements specified in Annex B.

4.1.5 No additional requirements to EN ISO/IEC17025.

4.2 Quality system

4.2.1 Documents specific to the monitoring of stack-emissions shall include:

a) standards published by national and international standards makingorganisations;

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b) MCERTS Method Implementation Documents (MIDs) outlining the Agency’sinterpretation of standard methods;

c) technical procedures providing detailed instructions on how standard methodsand any MCERTS MIDs, including guidance on implementation in TechnicalGuidance Note M2, shall be performed;

d) a site review to ensure that the organisation understands the physical andlogistical situation before arriving on-site to conduct work;

e) site-specific protocols, which show how the technical procedures are to beemployed in a given situation;

f) a risk assessment detailing hazards and associated risks;g) a work file detailing the stack measurement campaign for an individual site;h) a standardised report providing sufficient detail to allow an audit trail back to

the on-site measurement and process plant operating conditions pertaining atthe time.

4.2.2 – 4.3.3.4 No additional requirements to EN ISO/IEC 17025.

4.4 Review of requests, tenders and contracts

4.4.1 - 4.4.5 No additional requirements to EN ISO/IEC 17025.

4.5 Subcontracting of tests (monitoring activities)

Organisations are permitted to subcontract monitoring activities to anotherorganisation accredited under MCERTS for that work. It is the responsibility of theorganisation to ensure that the subcontracted organisation is accredited underMCERTS for the scope of work. If analytical work is subcontracted, it shall be to anorganisation that has accreditation to EN ISO/IEC 17025 for the scope of work.

Where individuals are employed on a subcontracted basis by an organisation, theorganisation shall ensure that the individual is certified under the MCERTS personnelcompetency scheme to the required level.

4.6 – 4.11 No additional requirements to EN ISO/IEC 17025.

4.12 Control of records

4.12.1 General

4.12.1.1 No additional requirements to EN ISO/IEC 17025.

4.12.1.2 Records of all original observations, including process plant conditions such astemperature, pressure, flow rate, feedstock, environmental conditions such as ambienttemperature, weather conditions and monitoring data shall be retained in accordancewith the requirements of the competent body.

4.12.1.3 – 4.14.2 No additional requirements to EN ISO/IEC 17025.

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5 Technical requirements

5.1 General

5.1.1 – 5.1.2 No additional requirements to EN ISO/IEC 17025.

5.2 Personnel

Monitoring organisations shall use personnel with the appropriate MCERTScertification to undertake stack-emission measurement (see the MCERTS personnelcompetency standard).

Note - the MCERTS standard defines three levels of competence - an entry level (trainee), Level 1(technician) and Level 2 (team leader). Personnel with Level 2 certification are permitted to lead astack-emission monitoring team, and approve site reviews, risk assessments, site-specific protocols andmonitoring reports. Personnel with Level 1 certification are permitted to carry out stack-emissionmonitoring as part of a team led by MCERTS Level 2 person. Trainees are only permitted to carry outstack-emission monitoring under the direct supervision of MCERTS Level 2 person.

5.2.1 – 5.2.5 No additional requirements to EN ISO/IEC 17025.

5.3 Accommodation and environmental conditions

5.3.1 Stack-emission monitoring requires equipment, reagents and samples to be protectedfrom damage during storage and transportation from an organisation’s permanent siteto the sampling area.

Note - details concerning protecting the integrity of samples and reagents during storage andtransportation may be specified in the relevant standard method; these may include storage out ofsunlight and at specified temperatures.

5.3.2 Sampling shall be undertaken at a suitable location with suitable facilities (see AgencyTechnical Guidance Note: M1).

Sampling is often undertaken at height in difficult conditions. A suitable platformshall be provided that meets the size and safety requirements for the monitoringexercise. Service requirements, such as electricity supply, shall also be taken intoconsideration. Portable lighting shall be used when appropriate to ensure safe workingconditions.

The organisation shall have procedures in place to ensure that environmentalconditions do not affect the measurement result. For example, temporary shelter shallbe used when appropriate to protect personnel, equipment and monitoring operationsfrom weather conditions .

5.3.3 Stack-emission monitoring has a high potential for contamination of samples. Theorganisation shall identify and assess the risk of contamination and a clean area shallbe available for setting up equipment and samples, recovering samples, and storingequipment and samples.

Note – a clean area may be defined in the sampling vicinity if the risk of contamination is low.

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5.3.4 Access to and use of areas affecting the quality of the monitoring shall be controlled.If necessary, the area for equipment set up and the work area shall be cordoned off sothat access to the sampling equipment and monitoring operation is restricted. Ifnecessary, a mobile laboratory shall be manned or otherwise secure so access isrestricted at all times.

5.3.5 The work area shall be cleared of trip hazards and obstacles. Mobile laboratories andtransport vehicles shall be kept clean and free from sources of contamination.

5.4 Test methods and method validation

5.4.1 General

Monitoring shall, where possible, be carried out in accordance with appropriatestandard methods (see Technical Guidance Note: M2) and instructions on theirimplementation.

The Agency is supplementing standard methods with Method ImplementationDocuments (MIDs), where it is necessary to provide details on how the preferredstandard methods shall be used for regulatory monitoring.

The stack-emission monitoring organisation shall use written technical proceduresaddressing the operation at the stack and the process conditions. The technicalprocedures shall follow the standard method and the MID, where available, to providegeneric procedures for undertaking a method. The technical procedure shall state howa method or group of methods shall be performed, providing supplementary materialclarifying technique, sampling and analysis policy, as well as detailed instructions onhow equipment shall be utilised, how data are to be recorded and how results are to bereported.

Note - UKAS will accredit organisations for the technical procedures to ensure they follow the standardmethods, MIDs and the requirements of EN ISO/IEC 17025.

Site-specific protocols shall be used to detail the application of the technicalprocedures to a specific site. Before conducting stack-emission monitoring, a personcertified to MCERTS Level 2 shall determine and propose a site-specific protocol thatis "fit for purpose" for the process and installation configuration. Approval shall besought from the competent authority if a standard method in an organisation’stechnical procedure requires modifying due to site-specific conditions.

If the method requires laboratory analysis of samples collected on-site the monitoringorganisation shall either be accredited for the analysis method to EN ISO/IEC 17025or shall use another laboratory accredited for the method.

5.4.2 Selection of methods

The choice of measurement method shall be carried out in accordance with thefollowing standards and relevant documentation:

• Agency Technical Guidance Note: M2;• Standard methods.

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If an appropriate CEN method is available, then this shall be selected. There is ahierarchy of monitoring standards that shall be used in the following order of priority:

• Comité European de Normalisation (CEN);• International Standardisation Organisation (ISO).

Note - when a CEN method is produced European Community member states must adopt it and anyequivalent method must be withdrawn. ISO methods are also commonly adopted, although this is not amandatory requirement.

If the substance cannot be monitored using methods covered by the above then amethod can be selected from any one of the following:

• American Society for Testing and Materials (ASTM);• Association Française de Normalisation (AFNOR);• British Standards Institution (BSI);• Deutsches Institute für Normung (DIN);• United States Environmental Protection Agency (US EPA);• Verein Deutscher Ingenieure (VDI).

When selecting a method, the organisation shall also take account of the followingrestrictions:

• the competent authority or legislation may specify the method for the specificinstallation;

• the suitability of the method (including the limit of detection) for determiningcompliance with the emission-limit value.

Note – the limit of detection may be stated in the standard method, if it is not stated it should be nogreater than 10% of the emission-limit value.

CEN Standards have often been validated for specific processes and conditions. Thesemay be used outside their scope of validation within specifications given in AgencyMIDs.

5.4.3 Laboratory developed methods

An in-house method developed by the organisation may be used in place of a standardmethod if it is fully validated in accordance with the requirements of EN ISO/IEC17025. The method developed by the organisation shall be validated to ensure it hasthe equivalent quality to a CEN Standard method. Laboratory developed methods usedin place of standard methods shall be implemented using a technical procedure that isUKAS accredited.

5.4.4 Non-standard methods

If a method requires developing to monitor a substance not covered by a standardmethod, the organisation shall develop the method in accordance with therequirements of EN ISO/IEC 17025. These methods shall be implemented using atechnical procedure which is UKAS accredited.

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5.4.5 Validation of methods

5.4.5.1 – 5.4.5.3 No additional requirements to EN ISO/IEC 17025.

5.4.6 Estimation of uncertainty of measurement

5.4.6.1 – 5.4.6.3

The organisation shall have procedures in place for providing an estimate of theuncertainties relating to results.

The stated uncertainty of a standard method can only be achieved if the exactingrequirements of the standard method are complied with in full. When a standardmethod is not complied with in full or a non-standard method is used, the followingapproaches shall be used, depending on the situation to estimate uncertainty:

• repeat measurements on reference materials;• experimental work, for example, repeatability experiments, paired comparisons

and ring tests;• estimations based on previous results/data e.g. instrument specifications,

calibration data, proficiency-testing schemes;• estimations based on considered judgement.

Estimating based on considered judgement shall be the method of last resort.

When there is no standard method available the organisation shall provide as much ofthe above information as possible and calculate an estimate of the overall uncertaintyattached to the measurement according to ISO 14956.

5.4.7 – 5.4.8 No additional requirements to EN ISO/IEC 17025.

5.5 Equipment

5.5.1 No additional requirements to EN ISO/IEC 17025.

5.5.2 Procedures shall be in place to ensure that equipment is appropriate to the process-specific environment where it is to be used.

The equipment shall meet all the criteria specified in the standard method being used.

In cases where no equipment specifications are given, the equipment shall satisfy thefollowing requirements:

• be non-reactive to the pollutant being monitored;• not cause any positive or negative interference to the monitoring operation;• have sufficient strength to withstand the environmental conditions (for

example, vibration, heat, shear forces, flex and abrasion) associated with theprocess being monitored.

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Note – specific requirements for equipment should be confirmed as part of the site review.

5.5.2 - 5.5.3 No additional requirements to ISO/IEC17025.

5.5.4 The identification of equipment shall be in an accessible location for viewing and itshall be etched, stamped, or otherwise permanently fixed to the component.

5.5.5 A record of the monitoring and sites where stack-emission monitoring equipment hasbeen used shall be maintained.

5.5.6 EN ISO/IEC 17025 recognises that additional procedures may be necessary whenmeasuring equipment is used outside the permanent laboratory for tests and sampling.

Organisations shall have procedures in place to ensure that equipment transported tosite remains within valid calibration. If there is any doubt, the equipment shall becalibrated on-site.

Leaks in sample trains shall be eliminated as far as practicable.

Where possible, mechanical connections shall be rigid and provide a positive sealwhen tightened. Gasket material shall be non-reactive to the gas being measured andable to withstand the prevailing operating temperatures without degrading.

Note - stack sampling equipment generally comprises several pieces of apparatus (for example, probes,filters, traps, pumps, meters) connected together to form a ‘sampling train’. The equipment is connectedtogether on-site.

Contamination and deterioration of equipment shall be assessed and dealt with in aplanned manner. The specifications given in standard methods shall be followed. Ifspecifications are not detailed in a standard method, the following practices shall befollowed. Components and equipment exposed to the sample stream shall bethoroughly cleaned and dried, including the sample media area, prior to conductingsampling. If performing multiple runs with the same equipment, the sample train shallbe cleaned between runs. Cleaning shall be performed using appropriate methods,tools and solvents to ensure that residue is removed and to prevent contaminating orotherwise affecting the sample. The organisation’s technical procedure shall specifythe cleaning procedure.

5.5.7 – 5.5.9 No additional requirements to EN ISO/IEC 17025.

5.5.10 Before monitoring commences, the equipment shall be subject to operational andquality checks in accordance with the relevant measurement standard.

Note - examples of good practice are given in Annex C.

5.5.11 – 5.5.1 No additional requirements to EN ISO/IEC 17025.

5.6 Measurement traceability

5.6.1 – 5.6.2.1.2 No additional requirements to EN ISO/IEC 17025.

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5.6.2.2 Testing

5.6.2.2.1 All aspects of the monitoring procedure shall be sufficiently prescribed andimplemented in a controlled manner so that the uncertainty of the results can bedetermined in a valid and rigorous way.

The organisation shall hold nationally-traceable calibration artefacts (where available)for all aspects of the monitoring process where inaccurate calibrations would affect thevalidity of the overall measurement uncertainty of the results.

Note – calibration gas mixtures are acceptable where they are obtained from a commercial companywith a calibration accreditation for the supply of the specific calibration gases required, or directly froma recognised national standards laboratory. It is not necessary for gases obtained from a nationalstandards laboratory to be used for routine or everyday quality assurance/quality control checks, sincethis may not be cost-effective. Instead, these should be used for regular checks on the concentrations ofmore routinely used gas mixtures where these are utilised.

The organisation shall participate in proficiency testing or a similar intercomparisonactivity where this is available, to demonstrate that the results obtained and theirmeasurement uncertainty are valid (see paragraph 5.9).

5.6.2.2.2 – 5.6.3.4 No additional requirements to EN ISO/IEC 17025.

5.7 Sampling (monitoring)

5.7.1 Stack-emission monitoring consists of sampling, analysis and reporting of results.

Note – analysis may occur on site using a direct reading instrument or at a later date at an organisation’spermanent facility or a subcontracted laboratory.

Sampling takes place as part of a measurement campaign. This requires a site reviewand risk assessment to be carried out and a site-specific protocol to be produced.Information specific to the measurement campaign shall be kept in a work file.

A measurement series shall be carried out under the conditions specified in the site-specific protocol. The organisation shall obtain confirmation from the operator that theprocess conditions specified were applicable during monitoring.

a) Site reviewStack monitoring personnel need to understand the physical and logistical situationon-site before commencing work. Before stack-emission monitoring is undertaken, asite review shall be undertaken and documented. This shall include an exchange ofinformation with the process operator to provide and obtain information relevant to thework.

The review shall provide essential information for determining an appropriatemeasurement method and developing a site-specific protocol. The review shall includea risk assessment.

A person certified to MCERTS Level 2 shall approve the site review. This person,however, need not be a member of the monitoring team. Information collected duringthe visit shall be conveyed to the team before commencing work.

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Note 1 a person certified to MCERTS Level 1 is permitted to conduct a site review but only under thedirect supervision of the Level 2 person who approves the review (see MCERTS personnel competencystandard).

The monitoring work shall not commence until any remedial actions documented bythe site review have been implemented.

Note 2 it is advisable to allow sufficient time between the site review and the planned measurementcampaign for any remedial actions to be completed and to enable a detailed site-specific protocol to bedeveloped.

The site review may be abbreviated on repeat visits to the site once the organisationhas full knowledge/experience of the particular site, including the specificrequirements of the work in hand. However, a risk assessment shall be carried out atthe beginning of every visit.

To prevent any critical items being overlooked, the organisation shall prepare achecklist of items that shall be evaluated. Annex D provides a list of items that shallbe evaluated and determined during a review and included in the organisation’schecklist.

b) Risk assessmentAn assessment of the hazards and associated risks involved in stack-emissionmonitoring shall be undertaken and documented during a site review and before everymeasurement campaign. The requirements specified in Annex B shall be followed.

c) Site-specific protocolEN ISO/IEC 17025 requires a sampling plan to address the factors to be controlled ormonitored to ensure the validity of monitoring results. The sampling plan is referred toas the site-specific protocol in this standard. A person certified to MCERTS Level 2shall approve the site-specific protocol. The factors relevant to stack-emissionmonitoring that shall be included in the site-specific protocol are contained in AnnexE. The site-specific protocol shall be updated, if required, to include feedback fromeach visit.

Note – when emission monitoring is undertaken for regulatory purposes, the site operator is normallyrequired to submit the site-specific protocol to the competent authority.

d) Work fileA work file shall be used to record the details of a stack measurement campaign. Fordetails required in a work file, see Annex F.

e) Monitoring record sheetsThe organisation shall have procedures for recording monitoring data and operationsrelating to stack-emission monitoring. Monitoring record sheets shall be used torecord this information. These shall be included as part of the final monitoring report.For details required on monitoring record sheets, see Annex G.

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f) BlanksWhen monitoring is undertaken requiring analysis of samples, sample blanks shallalso be analysed and reported. Many standards specify the procedure for blanks. Formethods where the taking of blanks is not addressed, instructions in the MCERTSMID shall be followed, where available. Guidance on blanks is also available inTechnical Guidance Note: M2, which states that as a minimum an overall field blankshall be produced for each measurement series and at least once per day.

g) Sample recoveryFor certain techniques, samples need to be recovered at the end of the measurementbefore they are analysed. In this case, sample recovery shall be carried out on-siterather than at a permanent laboratory.

Sample recovery shall not affect the integrity of the result. Sample recovery shall beundertaken according to the specifications of the standard method, MID and theorganisation’s technical procedure. The technical procedure shall state the reagents touse (for example, water, toluene or acetone) and the cleaning technique (for example,brushing or rinsing).

5.8 Handling of test items

5.8.1 The transport of stack gas from the stack to an analyser shall not affect the integrity ofthe result.

Collected samples shall be maintained under environmental conditions that do notalter the integrity of the result. For regulatory purposes, a chain of custody record shallbe maintained from the collection of samples, to sample storage, to sample analysis.The record shall detail who has possession of the samples and the location of theitems.

5.8.2 In stack-emission monitoring, the test item includes the stack, which shall beidentifiable by a specific reference number. This number shall be consistent with anyidentification specified by the competent authority and/or site operator.

5.8.3 Any deviations from a method caused by stack sampling facilities not conforming tothe method requirements (for example, access restricted to one port) shall be recorded.Platform specifications are contained in Technical Guidance Note: M1.

5.8.4 No additional requirements to EN ISO/IEC 17025.

5.9 Assuring the quality of test results

Proficiency-testing (PT) schemes shall be used where available.

Note - current schemes include:• the instrumental analysis of standard gas mixtures;• the use of a reference device with known operational characteristics to determine the proficiency

of measuring physical parameters such as flow, velocity, temperature and the like;• the use of monitoring sites with known characteristics;• the use of a flow-testing scheme.

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The results obtained from such PT schemes are a snapshot of the organisation’scapabilities, and shall be used to assess whether the organisation is complying with itsclaimed measurement uncertainties. This information shall be made available toUKAS, which will keep the competent authorities informed. If these are non-compliant, the organisation shall take steps to ensure adequate improvements areimplemented.

5.10 Reporting of results

5.10.1 General

A standard report format shall be used for regulatory compliance monitoring.

5.10.2 Test reports (monitoring reports)

A monitoring report shall include a description of the condition of, and unambiguousidentification of, the item(s) monitored. An organisation shall unambiguously identifythe substance, material or product measured. This refers to the stack and the stack gasbeing sampled. A stack shall be uniquely identifiable. A diagram of the stackdimensions shall be included in the report.

Stack-emission monitoring results shall be reported at standard reference conditions oftemperature and pressure. It may also be necessary to report stack-emissionmonitoring results as a dry gas and at reference oxygen concentrations. The referenceconditions shall be recorded on a stack-emission monitoring report.

For information required in a monitoring report see Annex H.

5.10.3 Test reports (continued)

5.10.3.1 The organisation shall confirm with the site/process operator that the processconditions under which sampling has occurred meet the requirements stipulated in thesite-specific protocol (the exact requirements are normally specified by the competentauthority in the permit). The monitoring report shall confirm that the requirementshave been met. For details of the types of process conditions that shall be recorded,see the report template in Annex H.

The monitoring report shall specify the conditions (temperature and pressure) of thestack gas being sampled and supporting environmental conditions.

5.10.3.2 No additional requirements to EN ISO/IEC17025.

5.10.4 No additional requirements to EN ISO/IEC17025.

5.10.5 Opinions and interpretations

Reports detailing results of regulatory compliance monitoring shall not containopinions or interpretations on whether the results demonstrate compliance or not withemission limit values.

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5.10.6 – 5.10.9 No additional requirements to EN ISO/IEC 17025.

6 Status of this document

6.1 This MCERTS performance standard may be subject to review and amendmentfollowing publication of this document. The latest version of the standard, togetherwith guidance on the scheme, is available on the Agency’s website at:

www.environment-agency.gov.uk/business/mcerts/.

6.2 If you have any questions regarding the accreditation process, including how to makean application, please contact UKAS at the address given in the foreword to thisdocument.

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Annex A - Environmental policy

A1 Good practice should ensure that the organisation’s activities do not harm theenvironment.

A2 Stack-emission monitoring organisations should conduct their activities and operationsto reflect best environmental practice. This can be achieved by implementing anenvironmental management system to pursue sustainability and continuousimprovement, as well as seeking ways of meeting environmental objectives.

A3 Particular care should be taken with the use of chemicals required for stack-emissionmonitoring.

A4 The environmental policy should address the following:

• use of fuel-efficient vehicles;• refrigeration in vehicles should use coolants that do not harm the environment;• sample containers should be recycled wherever possible;• reports should be on 100% post-consumer waste paper or in electronic format

if acceptable to the client’s requirements;• batteries for sampling equipment should be rechargeable and (where possible)

recyclable;• equipment to be returned to manufacturer at end of useful life to be

disassembled and parts re-used where possible;• calibration and cleaning of equipment should avoid using solvents contributing

to ozone depletion/global warming.

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Annex B - Health and safety

B1 Relevant safety guidance shall be followed, for example, Agency Technical GuidanceNote: M1, STA publication Hazards, Risk and Risk Control in Stack TestingOperations.

B2 The monitoring organisation shall implement procedures to minimise health and safetyrisks during site work. The procedures shall include:

• using a risk-management approach to site work;• compliance with care of substances Control of Substances Hazardous to Health

(COSHH);• site-safety induction training;• safe systems for lone and remote working.

B3 Equipment used on-site by the organisation shall meet all the necessary safetystandards required. Monitoring personnel shall use appropriate lifting equipment. As aminimum personnel shall wear safety glasses and steel toe-capped footwearconforming to appropriate standards while undertaking stack-emission monitoring.

Note – equipment used on-site by the monitoring organisation also includes any of the operator’sequipment they may use (for example, lifting equipment).

B4 Appropriate control measures (for example, safe working procedures, local exhaustventilation and personal protective equipment) shall be detailed in the organisation’stechnical procedure for the relevant methods.

B5 The monitoring organisation shall undertake and document a risk assessment specificto the required work and sampling location. This shall be undertaken in three stages:

• as part of a site review;• before pre-sampling preparation in the laboratory;• before to on-site monitoring.

B6 The site review risk assessment shall include a section that shall be completed beforeentering the area of work. This shall be used by the monitoring organisation to find outstandard site safety information such as fire alarms and procedures, chemical hazardalarms and procedures, intrinsically safe working areas, hygiene regulations and thelike. This information may be covered in a formal site induction or a permit to worksystem. On sites where these are not available, it is the responsibility of the personcertified to MCERTS Level 2 (team leader) to obtain the information.

B7 The monitoring organisation’s risk assessment shall confirm that the site/processoperator has the following elements in place before undertaking stack-emission work:

• a safety policy covering work on site in accordance with the requirements ofthe Management of Health and Safety at Work Regulations;

• a safe sample platform and work area.

B8 Monitoring personnel visiting or working on a site for the first time shall attend a siteinduction if provided by the site operator. Attendance at an induction shall be recorded

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on the risk assessment for each member of the monitoring team.

B9 The risk assessment shall include an assessment of the level of risk from each of thevarious hazards present and as a minimum shall include:

• general site hazards – site traffic, fire and emergency, mechanical operations,chemical operations;

• physical hazards at the stack – lifting, falling, burns, electricity, compressedgases;

• chemical hazards at the stack – exposure to substances from flue gases,exposure to substances used in monitoring tests;

• weather and environment – temperature extremes, wind, rain, lightning, snowand ice, sunburn;

• chemical hazards at the laboratory – exposure to chemicals used for equipmentand sample preparation.

B10 The risk assessment shall also include:

• a COSHH assessment of exposure to workplace substances (both laboratoryand on-site);

• information on the composition and pressure of the gas in the stack to bemonitored and the process characteristics;

• identification of the control measures are required to reduce exposure to anacceptable level.

B11 Organisations that undertake lone working on-site shall incorporate safety proceduresinto the risk assessment (for example, use of personal alarm, regular contact with sitepersonnel).

B12 The risk assessment shall clearly show the hazards for each working area (for examplemonitoring position, stack and the like).

B13 The risk assessment shall include whether the risk is negligible, as low as isreasonably practicable (ALARP) or unacceptably high. The level of risk shall be thatrecorded at the time of assessment, not the level that would be the case if controlmeasures were put in place.

B14 The operator shall be shown the risk assessment and be given the opportunity tocomment on it. For in-house teams, a representative of the operator not directlyinvolved in the work shall be shown the risk assessment. Typically, this could be theenvironmental manager or safety manager.

B15 Work shall not commence until the organisation’s risk assessment confirms that therisks are ALARP, or control measures have been put into place (including those thatare the responsibility of the operator) to reduce the risk to an acceptable level(negligible, ALARP).

B16 Before work commences, the risk assessment shall be communicated by the Level 2person (team leader) to other members of the monitoring team. All team members signthe risk assessment to confirm they have seen and understood its content.

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Annex C - Equipment calibration

The following gives details of good practice regarding the on-site calibration of stack-emission monitoring equipment.

C1 Equipment should undergo operational checks to ensure it is functioning correctlybefore and during use (for example, correct indicator lights on analyser, pumpoperating, heated sample line at correct temperature).

C2 Instruments that are subject to calibration shifts during transport or during monitoringshould be subject to on-site calibration. In such cases it is not sufficient to reference acalibration made in the laboratory before taking the instrument to the site.

C2 Instruments used to measure physical parameters (for example, flow meters) should, ifappropriate, be checked on-site against a known standard such as a critical orifice.

C3 The range of instrumental analysers should be selected to ensure that, as far aspracticable the upper point of the range is twice the emission limit value for thesubstance being measured.

C4 Instrumental analysers are calibrated using a zero gas and a span gas. The span gasconcentration is equivalent to the emission limit value of the substance beingmeasured.

C5 Zero and span checks should be carried out on instrumental analysers on-site before,after and if required during measurement using traceable gases of knownconcentrations. The results of the calibration check should be reported, with the dataindicating the difference between the analyser’s reading and the known value of thestandard.

C6 If the span and zero drifts are within the specified tolerances of the applicable standardmethod, the measurement run is acceptable and the results may be reported. If thedrifts exceed the allowable tolerances, then the instrument should be re-calibrated andthe measurement repeated.

C7 The zero and span gas calibrations should confirm the integrity of the completesampling system by being introduced into the system in accordance with theapplicable standard method.

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Annex D - Site review

D1 At each stage of the site review, health and safety shall be considered and the riskassessment completed.

D2 Factors that shall be included in a site review are:

Site information• address and contact information;• general information about the process;• scope of work;

Process conditions• process characteristics (material balance, process-flow diagrams, feedstock

details and the like);• expected emissions (concentration or mass);• expected process variations;• site instrumentation relevant to the monitoring process;• emission control equipment (type, operating mode, instrumentation, control

arrangements);

Sampling location• access to the stack;• adequate work area at the sampling positions;• availability of required utilities (electrical, lighting, water);• sample ports (accessibility, correct size, sufficient number, properly located);• the stack dimensions at the sampling location;• a pitot tube traverse of the velocity profile;• temperature and moisture of the stack gas;• diagram of the sampling point locations and stack geometry;• site restrictions on using equipment, for example intrinsically safe areas;• physical and chemical restrictions to using equipment;• chemical composition of stack gas;• determine appropriate monitoring equipment for the application.

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Annex E – Site-specific protocol

The following details shall be addressed in a site-specific protocol:

• the site name, address and operator contact;• the planned date of the measurement campaign;• the names of sampling team members, their competency and specific

responsibility;• the type of process;• a description of the site;• the identity of the installations to be measured;• the operational/ feed details, for example, continuous, batch process;• the duration of any batch processes;• for non-continuous processes, the part of the process when sampling will take

place;• any unusual occurrences that take place during the process;• the process details that need to be collected over the monitoring period;• the emission-limit values;• expected emission values;• the substances to be monitored at each installation;• the reference conditions for reporting concentrations;• the measurement method for each substance;• the organisation’s technical procedure reference covering implementation of

the above method;• the overall uncertainty of the technical procedure;• any modifications to the technical procedure, with justifications and any

resulting changes to the uncertainties;

Note - where the operator or competent authority requires deviations, additions or exclusions from thedocumented sampling procedures, these must be recorded in detail to satisfy the requirements of ISO17025 on sampling (ISO 17025, 5.7).

• the equipment used for each substance monitored;• the sampling duration and number of samples for each measurement, including

blanks;• for manual methods, the proposed sample flow-rate, volume and minimum

sampling times;• for instrumental methods, the proposed span-gas concentration;• the measurement concentration range and lower detection limit;• a description of the location of the sampling plane for each release point;• for each sampling plane, a description of the type of sampling port;• for each sampling plane, a summary of the number, arrangement and

orientation of the sample line(s), and the number of sampling points per line;• for each sampling plane, a summary of compliance with CEN Standards;

Note – a statement of compliance with CEN Standards is required to satisfy the requirements of ENISO/IEC 17025 on control of non-conforming tests (ISO 17025, 4.9).

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• for manual methods requiring a separate chemical analysis stage, details of theanalytical method, the laboratory carrying out the analysis, chain-of-custodydetails, allowable time for transit to the laboratory, storage conditions andarchiving requirements;

• the procedure for recording monitoring data;• the method to be followed for correction of results to standard conditions;• the report format, the person who will be writing the report and the person who• will be checking the report;• the procedure for checking data quality;• the date the results report is due to be issued;• the reference number and date of the on-site health and safety risk assessment

the team carried out;• the reference number of the use of hazardous chemicals risk assessments for

each measurement method;• any site-specific safety requirements, for example, local safety induction

course, intrinsically safe site;• any other relevant health and safety requirements.

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Annex F - Work file

A work file shall contain the following:

• site-specific protocol;• site review;• risk assessment;• equipment checklist, including reference to equipment history file;• volume of reagents and amount of sample media required;• forms used by the site operator;• site calculation and data sheets;• record of process conditions at time of monitoring;• record of deviations from the approved site protocol.

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Annex G - Monitoring records

Monitoring records shall include:

• the date;• the names of the monitoring team members making the records;• the measurement procedure used;• the identification of the equipment;• the sampling location (including diagrams as necessary);• environmental conditions, for example, atmospheric pressure;• details of measurement start and finish times;• for manual methods, details of sampling, for example, dry gas metre readings,

solution volumes, pressure and temperature readings;• for manual methods, the sample details, for example, sample bottle or sorbent

tube identification label;• for instrumental methods, the zero and span gas verification results;• for instrumental methods, the output or indicated readings of the analyser.

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Annex H – Stack-emission monitoring report

A stack-emission monitoring report shall include the following information on each page:

• a unique reference in the following format: - Agency reference number (if carrying out work for the Agency); - permit number; - operator and installation name; - year of the monitoring visit; and - sequential number of the visit in the year (if applicable).

• a version number; and• a page number, which shall be written as “page x of y”.

The report shall contain the following information in the order specified:

Part 1: Executive Summary

Cover Sheet• MCERTS logo, the UKAS logo and registration number of the monitoring organisation;• title;• permit number;• operator name;• installation name;• dates of the monitoring visit;• contract number or reference;• name and address of the client organisation (where applicable);• name and address of the monitoring organisation;• date of the report;• name, MCERTS registration number and the function of the person approving the report

for the monitoring organisation; and• the signature of the person approving the report

ContentsThe content sheet shall describe the contents of both parts of the report.

Monitoring Objectives• the overall aim of the monitoring campaign;• the substances to be monitored at each emission point; and• any special requirements.

Monitoring Results• emission point;• substances to be monitored;• emission limit value expressed in the terms and units defined in the permit;• periodic monitoring result in the same terms as the emission limit value;• uncertainty associated with the result at a 95% confidence level;• units for the emission limit value, the periodic monitoring result and the uncertainty;• reference conditions at which the results are expressed;• date of monitoring;

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• start and end times for the monitoring;• name and reference number of monitoring method used;• accreditation for use of the method, such as MCERTS, UKAS; and• process status at the time of monitoring, such as load and feedstock.

Operating information• whether process was continuous or batch process;• whether the whole of the batch was sampled or the details of the part of the batch sampled

(if applicable);• what fuel was used during monitoring (if applicable);• what feedstock used during monitoring (if applicable);• the normal load, throughput or continuous rating of the plant;• what type of abatement system and whether operating; and• the periodic monitoring results and the results obtained for the corresponding period by

the operator’s CEMS.

Monitoring Deviations• an explanation why any substance(s) in the monitoring objectives was not monitored;an explanation why any substance(s) were not monitored in accordance with the monitoringmethod stated in Environment Agency TGN: M2; andany other issues relevant to the monitoring results

Part 2: Supporting information∗

Cover sheetThe cover sheet for Part 2 should contain the same information that is detailed in the Part 1cover sheet.

ContentsThe contents sheet shall describe the contents of the whole report.

Appendix 1• the names, MCERTS registration numbers and the functions of those persons engaged in

the monitoring of the installation;• the substance(s) monitored, the reference number of the standard method used and the

reference to the Technical Procedure used by the monitoring organisation; and• a reference to the equipment check lists used on the monitoring campaign.

Further appendices (one for each emission point)• diagrams showing the dimensions of the stack and the monitoring facilities;• flow criteria measurements, such as measurements for temperature, pressure and stack gas

velocity;• gas measurements, such as oxygen and carbon dioxide;• water vapour measurements;• sampling measurements, such as stack gas temperature and velocity during sampling;

∗ If the client agrees the monitoring organisation may provide them with only Part 1 (Executive Summary) of themonitoring report. However, Part 2 must be retained at the monitoring organisation’s premises and be availablefor auditing for a minimum of 4 years.

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• instrumental gas analyser site calibration measurements including zero and span gasconcentrations;

• instrumental gas analyser results;• analysis sheets including the name of the analytical laboratory, the accreditation for the

use of the analytical method and the date of the analysis;• the manual monitoring method results calculations, including concentrations and mass

emissions; and• uncertainty calculations.