ICE Health Summit,
Workshop B, Description & Outputs Facilitator, Kelvin Williams, BoHS Assisted by Karen Young, Scottish Water Rapporteur, Peter Crosland, CECA Introduction In essence, Workshop B set out to achieve the following objectives;-
Inform what does an occupational hygienist do? (this will focus on occupational hygiene in design/construction)
Determine what Control measure priorities
Consider the complexities of selecting control measures that are proportional to the risk
Understand how occupational hygienists contribute to competent design and worker health protection
The Workshop was preceded by a short presentation – See Appendix 1 Workshops The Workshop questions were made up from 2 different scenarios; 1 & 2. These were provided in template format for attendees to complete. See Appendix 2 for blank Templates and Appendix 3 populated templates. Scenario 1 A Sprayed Concrete Lining Technique will be used to construct several kilometers of tunnels. Using robotic spraying rigs, the SCL will be applied to surfaces to provide reinforcement of excavated surfaces. The process is one of continuing excavation, mucking out, spraying concrete, allowing to cure, breaking out and excavating further. The SCL technique involves wet application of a primary lining, waterproofing and application of a secondary lining (will often need to be dry applied). Summary of Feedback
“What information would be helpful to ensure cost effective dust control ie; controls that are proportional to risk and applied where necessary”. Many comments related to a better understanding of risk so that the operator can be assured that control measures are proportional, cost effective - and that they work! Several other comments reflect an appreciation of the utility of the occupational hygiene knowledge base, ie; awareness of range of risks, experience of exposure levels on similar works elsewhere and what controls work best, etc. Feedback also included OH’s to provide advice on the following;- • O/H to recognise where hazard exists • O/H to advise ‘is it worth worrying about’? • OH to do/advise on sampling to determine what control measures might be needed • O/H to advise what they can bring to the process? Other Comments;- • Purpose of regulations is to CONTROL hazardous substances - not just agreeing monitoring. • Ask for initial data regarding hazards of the process. • Need to check for pre-existing data in order to provide baseline for further assessment. • Design to take place prior to the contract starting. • Need to know dust size (particles). • Need to know exposure time. • Need Area/size of workplace. • COSHH assessments needed on materials. • Need background air monitoring and safety level monitors. • Arrangements of LEV including check effects of noise/emissions from LEV solution. • Provide automated ‘Canary’ to show when levels of dust are too high. • Quantify dust and emissions from each task (quantity of silica content too). • Look at going back to the design – how can the source problem be designed out? • Continuous monitoring is require to provide the fuller picture. • Fire not considered – there needs to be a means of escape away from the potential fire hazard. • Don’t use monitoring as a panacea – there needs to be CONTROL • LEV – Provision is not always proportional to risk. Need to understand how to optimise (maximise?) LEV provision.
• Attend BoHS course – need to up-skill ALL H&S professionals. • Quantify dust emissions from each test then quantify cost for each applicable measure – they are interdependent. • Effectiveness of filtration around workplace needs to be understood. • Testing regime of control measures needs to be established prior to being put into use. • Use of precast units could give rise to additional risks during transportation & installation. • Measure workplace before any one enters. Scenario 2 A reinforced concrete slab will be laid as a foundation to a new biomass plant. Concrete will pumped from a concrete pumping vehicle situated beside the foundation slab. There will be several staff engaged in controlling the pour and manually spreading the concrete using vibrating pokers and walk behind power trowels and levellers. The work will be carried out over a period of two weeks. Summary of Feedback “What information would be helpful to ensure cost effective control of noise and vibration exposure ie; controls that are proportional to risk and applied where necessary”. Overall the responses were similar to those received under Scenario 1 . However, specific comments to Scenario 2 are given below;- OH to Provide Advice on the following;-
OH can could advise if control measures are reasonably practical
OH can advise on appropriate hearing protectors, job rotation time limits, distance
from noise source.
OH can help by developing a strategy for monitoring effectiveness (of measures)
OH can bring previous experience – what worked before including useful data to
increase level of confidence of what is proposed.
OH to advise if control measures are achievable/reasonable/manageable?
OH to advise what level/limits of vibration and noise workers are allowed to work
in?
OH to advise who might be affected by noise on the site.
OH could provide information on HAVS including (noise) i.e levels / measurements
etc. to from part of Handling Management Strategy
OH to advise on MSD impact of manual handling.
OH to advise on potential for spread of noise and vibration from each tool.
OH to provide advice and suitable information on technology for low vibration and low noise tools.
Miscellaneous Comments
Actual levels of vibration not known as data from manufacturers not always to be
believed.
Consider use of additives to improve consistency and flow of concrete and to limit
(reduce?) use of vibrators etc.
Consider whether the (noise) controls protect everyone working on the site.
Feedback cost of monitoring and measurement into a Business Case in support of
automation.
Need to consider whether this activity is a one off - but even then workers might
be doing same activity on other jobs – need to carry out health surveillance!
APPENDIX 1 = Presentation Slides Slide 1
Recognise Evaluate Control
Occupa onalHygiene
Slide 2
Slide 3
3 way partnership
Occupa onalHygieneProtec ngpeople
fromworkplacehealthrisks
Promo nghealthylifestylechoices
Wellbeing
ManaginghealthofworkersOccupa onal
Health
www.breathefreely.org.uk www.bohs.org
Controlling Exposures to
Prevent occupational lung disease
in the construction industry
Slide 4
Slide 5
www.breathefreely.org.uk www.bohs.org
Controlling Exposures to
Prevent occupational lung disease
in the construction industry
WellbeingHealth
SurveillanceRiskPreven on
&Control
www.breathefreely.org.uk www.bohs.org
Controlling Exposures to
Prevent occupational lung disease
in the construction industry
WellbeingHealth
Surveillance
Slide 6
Slide 7
www.breathefreely.org.uk www.bohs.org
Controlling Exposures to
Prevent occupational lung disease
in the construction industry
WellbeingHealth
SurveillanceRiskPreven on
&Control
Slide 8
How can an occupational hygienist help?
APPENDIX 2 – BLANK TEMPLATES Scenario 1 - Sprayed Concrete Lining Scenario: A Sprayed Concrete Lining Technique will be used to construct several kilometres of tunnels. Using robotic spraying rigs, the SCL will be applied to surfaces to provide reinforcement of excavated surfaces. The process is one of continuing excavation, mucking out, spraying concrete, allowing to cure, breaking out and excavating further. The SCL technique involves wet application of a primary lining, waterproofing and application of a secondary lining (will often need to be dry applied).
Hazard: The process is expected to create large amounts of airborne dust. There appears to be a particular risk of breathing in fine silica dust during breaking out of the concrete and excavation of the soil, as well as during spraying operations. It appears that everyone working in the tunnel might be at risk.
Select A Control Measure Discussion Prompt Is this control measure proportional to risk? Will it be an adequate
response, or are other supplementary measures required?
Substitution Use low silica materials
Process As far as possible, use pre-cast for secondary lining
Engineered Controls: Use local exhaust ventilation (dust extraction)
Engineered Controls: Water suppression
Administrative Controls Exclusion zones (keep distance from dustiest locations / signed RPE zone)
RPE Provide workers with a selection of disposable dust masks or air fed dust masks
Feedback: What information would be helpful to ensure cost effective dust control ie; controls that are proportional to risk and applied where necessary.
Scenario 2 – Reinforced Concrete Slab Scenario: A reinforced concrete slab will be laid as a foundation to a new biomass plant. Concrete will pumped from a concrete pumping vehicle situated beside the foundation slab. There will be several staff engaged in controlling the pour and manually spreading the concrete using vibrating pokers and walk behind power trowels and levellers. The work will be carried out over a period of two weeks.
Hazard: High noise levels from pumping plant and equipment is anticipated. There appears to be a risk of excessive hand arm vibration exposure for workers required to operate hand held powered tools. It appears that everyone working in the locality might be at risk from noise exposure.
Select A Control Measure Discussion Prompt Is this control measure proportional to risk? Will it be an adequate
response, or are other supplementary measures required?
Automate Eliminate requirement for use hand held power tools for spreading
Engineered controls Specify low vibration / low noise tools
Administrative controls Use job rotation to limit each individual’s exposure to vibration and noise
Administrative controls Ensure all tools are regularly inspected for damage / rattling parts etc.
Administrative Controls Keep a distance from noisy locations / establish hearing protection zone
Hearing protection Provide workers with a selection of hearing protectors
Feedback: What information would be helpful to ensure cost effective control of noise and vibration exposure ie; controls that are proportional to risk and applied where necessary.
APPENDIX 3 – SCENARIO 1, POPULATED TEMPLATE Role of Occupational Hygienist in Design and Construction Scenario 1: FEEDBACK SUMMARY – ALL SESSIONS (18) A Sprayed Concrete Lining Technique will be used to construct several kilometres of tunnels. Using robotic spraying rigs, the SCL will be applied to surfaces to provide reinforcement of excavated surfaces. The process is one of continuing excavation, mucking out, spraying concrete, allowing to cure, breaking out and excavating further. The SCL technique involves wet application of a primary lining, waterproofing and application of a secondary lining (will often need to be dry applied).
Hazard: The process is expected to create large amounts of airborne dust. There appears to be a particular risk of breathing in fine silica dust during breaking out of the concrete and excavation of the soil, as well as during spraying operations. It appears that everyone working in the tunnel might be at risk.
Select A Control Measure
Discussion Prompt Is this control measure proportional to risk? Will it be an adequate
response, or are other supplementary measures required?
Substitution Use low silica materials
The disadvantages of substitution Check the risks that might be introduced How the design will be affected Is such a material available? Manage exposure levels and carry out review You cannot substitute concrete; pull in a hygienist to help mitigate
as much as possible. O/H could benchmark old vs new? O/H will asses manufacturers risks against actual environment. Check is Case Studies available – hat is residual risk. Look at best idea vs cost? Additional measures needed?
Process As far as possible, use pre-cast for secondary lining
Reduces dust – how much? Hygienist can help but need ongoing, regular air monitoring
Question the decision to use sprayed concrete Potential problem with logistics and room to cater for pre-cast
units. Proportional to risk. Use precast. Adequate for scheme design but will need additional
measures for monitoring to check OK. Does method remove all/enough dust? Hygienist to confirm how
much? Agree – off site manufacturing to be encouraged.
Engineered Controls: Use local exhaust ventilation (dust extraction)
Check the environment and change it Use in sensible position Use previous data Applied where necessary. Extraction – levels to be minimum prior to entry. Look at filters, maintenance thereof, flow rate, training, dust &
health level monitoring, Check on position of extraction What LEV to choose – training needed for operatives to check
locations / emissions etc.
Engineered Controls: Water suppression
Data on similar exposure.
Administrative Controls Exclusion zones (keep distance from dustiest locations / signed RPE zone)
How to define the exclusion zone? How do we define safety zones? What data will define our decisions? Use system of Permit to Enter
RPE Provide workers with a selection of disposable dust masks or air fed dust masks
Types of masks?? Recommendations Recommendations for the safe methods of use. What is the residual risk? Would be role dependent – but check at regular intervals.
Feedback: What information would be helpful to ensure cost effective dust control ie; controls that are proportional to risk and applied where necessary. OH to provide advice on the following;-
O/H to recognise where hazard exists O/H to advise ‘is it worth worrying about’? OH to do sampling to determine what control measures might be needed O/H to advise what they can bring to the process?
Other Comments;-
Purpose of regulations is CONTROL of hazardous substances not just agreeing monitoring. Ask for initial data regarding hazards of the process Need to check for pre-existing data in order to provide baseline for further assessment. Design prior to contract starting. Need to know dust size (particles) Need to know exposure time. Need Area/size? COSHH assessments needed on materials. Need background air monitoring and safety level monitors Arrangements of LEV including check effects of noise/emissions from LEV solution. Automated ‘Canary’ to show when levels of dust are too high. Quantify dust and emissions from each task (quantity of silica content too) Quantify costs and risks of each measure. Look at going back to the design – how can the source problem be designed out? Continuous monitoring is require to provide the fuller picture. Fire not considered – there needs to be a means of escape away from the potential fire hazard. Don’t use monitoring as a panacea – there needs to be CONTROL LEV – Provision is not always proportional to risk. Need to understand how to optimise
(maximise?) LEV provision. Attend BoHS course – need to upskill ALL H&S professionals. Quantify dust emissions from each test then quantify cost for each applicable measure – they
are interdependent. Effectiveness of filtration around workplace needs to be understood. Testing regime of control measures needs to be established prior to being put into use. Use of precast units could give rise to additional risks during transportation & installation Measure workplace before any one enters.
APPENDIX 3 – SCENARIO 2, POPULATED TEMPLATE Role of Occupational Hygienist in Design and Construction Scenario 2: FEEDBACK SUMMARY ALL SESSIONS (23) A reinforced concrete slab will be laid as a foundation to a new biomass plant. Concrete will pumped from a concrete pumping vehicle situated beside the foundation slab. There will be several staff engaged in controlling the pour and manually spreading the concrete using vibrating pokers and walk behind power trowels and levellers. The work will be carried out over a period of two weeks.
Hazard: High noise levels from pumping plant and equipment is anticipated. There appears to be a risk of excessive hand arm vibration exposure for workers required to operate hand held powered tools. It appears that everyone working in the locality might be at risk from noise exposure.
Select A Control Measure Discussion Prompt Is this control measure proportional to risk? Will it be an adequate
response, or are other supplementary measures required?
Automate Eliminate requirement for use hand held power tools for spreading
Doesn’t address noise hazard Dependent on cost Use autonomous laying/screeding machine. Use of pre-casting. Consider quality of finish? Use self levelling concrete Potentially costly alternative – if available? Dependent on size of slab being poured and whether it’s a one
off. Do automated alternatives exist? Automation could be expensive just for a 2 week pour.
Engineered controls Specify low vibration / low noise tools
Yes – It would be part of a range of measures to manage the risks. Measurement of noise and vibration , selection of tools to reduce
levels ALARP then re-assess. Consider remote use Use vibrating attachments on formwork. Use of additives? Needs to be proportionate – OH to advise on potential for
dermatitis OH to advise on vibration levels of equipment and how this can
be measured. Pokers / powerfloats etc. Training on HAVS & Noise – Need to understand exposure
values. Need to consider pre-existing issues (health surveillance?) Remote control powerfloat Need to consider effect of tools on other workers on site. Consider effects of both design and procurement. Procurement to state low noise tools & equipment. Eliminate or reduce at source and use acoustic barriers.
Administrative controls Use job rotation to limit each individual’s exposure to vibration and noise
Hygienist to advise on appropriate job rotation Yes – this would need to be identified in the risk assessment. What is acceptable in terms of rotation and noise level? OH to advise on types of noise workers subjected to – (from
different activities) Use noise barriers? Job rotation most cost effective way approach – easily
communicated to operatives and easily controlled. Need to carry out tests and checks on operatives prior to works
commencing (surveillance!). Assess each individual worker to see how they are affected
differently by vibration – eg smokers vs non-smokers?
Administrative controls Ensure all tools are regularly inspected for damage / rattling parts etc.
Ensure accurate and true levels.
Administrative Controls Keep a distance from noisy locations / establish hearing protection zone
May not be feasible – hygienist to advise on distance from work location.
Limit the time frame/exposure - set up safe work zones.
Hearing protection Provide workers with a selection of hearing protectors
What about out of hours activities – minimise exposure if possible – schools??
Pre-works risk assessments
Feedback: What information would be helpful to ensure cost effective control of noise and vibration exposure ie; controls that are proportional to risk and applied where necessary. OH to Provide Advice on the following;-
OH can could advise if control measures are reasonably practical OH can advise on appropriate hearing protectors, job rotation time limits, distance from noise
source. OH can help by developing a strategy for monitoring effectiveness (of measures) OH can bring previous experience – what worked before including useful data to increase level
of confidence of what is proposed. OH to advise if control measures are achievable/reasonable/manageable? OH to advise what level/limits of vibration and noise workers are allowed to work in? OH to advise who might be affected by noise on the site. OH could provide information on HAVS including (noise) i.e levels / measurements etc. to from
part of Handling Management Strategy OH to advise on MSD impact of manual handling. OH to advise on potential for spread of noise and vibration from each tool. OH to provide advice and suitable information on technology for low vibration and low noise
tools. Other Comments
Actual levels of vibration not known as data from manufacturers not always to be believed. Consider use of additives to improve consistency and flow of concrete and to limit (reduce?)
use of vibrators etc. Consider whether the (noise) controls protect everyone working on the site. Feedback cost of monitoring and measurement into a Business Case in support of automation. Need to consider whether this activity is a one off - but even then workers might be doing same
activity on other jobs – need to carry out health surveillance!