Construction Health and Safety

1. Construction Health and Safety Trevor Pavitt All information contained in this presentation is confidential and the property of Alistair Gibb of Loughborough University. No part of this presentation may be duplicated without the author’s specific consent. The information presented has been shown in good faith. www.apache4change.com

2. Designers dangerously unaware of CDM duties SHP June 2003 Occupational health is a major problem for construction Between 2001 and 2002 79 people died in construction and there were 3959 serious accidents. Over the same period the HSE estimates that 137 000 construction workers suffered from ill-health caused, or made worse by their job (HSE, Building, 11 July 2003). We need to put the health back into health and safety Work-related ill-health is under-recognised, under-reported, under-diagnosed and under-managed (Dr Andrew Colvin, medical advisor to CTRL) Designers can make a difference Hazards are introduced at the earliest stages in a project’s life and can often be eliminated and risks reduced through the design process (CONIAC HSC/M1/02/3). But designers often don’t know what to do HSE found that a third of designers on major construction projects demonstrated little or no understanding of their responsibilities to design-out risks (SHP June 2003). D4h provides designers with an opportunity to make a difference to the occupational health of construction workers Vital to eliminate health hazards in design Lawrence Waterman, Sypol Building, July 2003 Designers unaware of their duties under CDM Croner July 2003 HSE targets consultants for ignoring safe design NCE March 2003 Designers face clamp down after safety blitz NCE May 2002 Clients and architect ignore safety Building 16 August 2002 Ill-health is like a slow-burning accident Kevin Myers, HSE Building July 2003 One in three designers ‘ignores safety’ Building May 2003 CDM: Confusion, Despair and Mayhem NCE July 2002 Designers ‘have no idea’ Construction News May 2003 Continue Alistair Gibb, Trevor Pavitt, Katie Horne, Roger Haslam APaCHe, Loughborough University ISBN XXX YYY 111 000

3. D4h – Designing for health Best practice exemplars Alistair Gibb Roger Haslam Katie Horne Trevor Pavitt

4. Recent APaCHe Projects • ConCA – Accident Causality • Better, easier, safer design • ECI SHE manual • ECI Health manual. www.apache4change.com

5. Current APaCHe Projects • D4h - Designing for Healthy Construction • HAVS - Hand-Arm Vibration study (CTRL) • Kerbs - Manual handling (CHSG) • CIRIA - Health Manual for Workers • HASPREST – H&S and Off-Site Production. www.apache4change.com

6. D4h – Designing for Health • Establishing best practice for designers reducing occupational health risks during construction • Developing strategy and guidance.

7. Why occupational health (OH) and the need to design-out hazards are both important.

8. Health and Design • OH is the poor relative of SAFETY • TMCS Directive (CDM) requires designers to act • OH can not be ignored • 79 fatalities in 2001-2002 • 3959 serious accidents • 137 000 OH cases.

9. Health and Design • Very little ‘good practice’ by designers • Only 33% had sufficient knowledge of their duties (HSE Survey) • Only 8% had had any training (HSE Survey) • It has been hard to find exemplars • But…. the supply-chain is innovating.

10. D4h Tool • Provides strategic guidance for the concept design phase • Provides element-specific guidance for the detailed design phase • Identifies main activities and health hazards • Suggests designer action to remove/reduce risk • Provides exemplars to illustrate the benefits.

11. D4h Process – Major Building D4h offers two distinct tools for designers: D4h outline strategy tool – Where the designer has the greatest opportunity to influence healthy design, but design details are not fixed D4h detailed design tool – Where healthy design is influenced by contractor and specialist input D4h Outline Design Strategy D4h Detailed Design Tool

12. Piling exemplar • Many health (and safety) hazards • Key health hazard from removal of pile top • Hand-held pneumatic breakers.

13. D4h Major Building – Pile top break down • Main piling activities • Main piling health risks • Pile top break down health risks • Innovations to reduce pile top break down health risks • Elliott pile break method • Recepieux pile break method • Taets hydraulic pile break method • Cementation-Skanska sacrificial guide wall

14. 1 2 3 4 5 6 7 D4h Major Building – Pile top break down Main piling activities 1 Auger fitted with appropriate head 2Auger drilled into ground to required depth 3 Concrete poured down hollow core of auger whilst auger is removed 4Steel reinforcement cage pushed into wet concrete 5Wet concrete overspill at ground level removed 6Ground level reduced and top section of pile ‘broken down’ to desired level 7 Pile cap or capping beam constructed.

15. 1 2 3 4 5 6 7 D4h Major Building – Pile top break down Main piling health risks 1 Manual handling aspects to changing auger heads 2Contaminated land hazards 3Dermatitis and other cement-related hazards 4 Manual handling and injury risks in placing rebar cage along with cement-related hazards 5 Cement related and manual handling hazards (excess concrete typically removed by hand) 6 Major hand-arm and whole body vibration hazards (HAVS/WBVS), noise, dust and other manual handling hazards 7 Insitu concrete hazards (many and various).

16. D4h Major Building – Pile top break down Main piling health risks Survey results from Designers/Planning Supervisors (APS Aberdeen and Newcastle 9/03)Red/Yellow - High risk Black/Blue - Medium risk Blue/White – Low risk

17. D4h Major Building – Pile top break down Pile top break down health risks • This image shows a real-life construction site situation In this case mostly poor practice • The boxes identify some of the main health hazards • Green boxes show where the site team have taken some action to reduce or control the risk • Red boxes show where they do not appear to have taken such action • In either case D4h aims to take action during design to avoid or reduce the risks before they reach site • This image was not taken from a project involving a D4h collaborator Ear protection to reduce risk from noise Eye protection to reduce risk from debris Site Helmets Skin cancer from excess sun exposure HAVS / WBVS from breaker vibration MSDs from bad posture and restricted work area Silicosis from cement dust Dermatitis from cement exposure Additional safety-related issues include: Injury from exposed reinforcement Unsecured ladder Struck by machine Falls / trips on debris PPE – eg boots, overalls, hi-visibility vests Undermining timber hoarding  Loughborough University Image courtesy Loughborough University

18. 1 2 3 4 5 D4h Major Building – Pile top break down Occupational Health Innovation Pile break method (Elliott) Main health issues addressed HAVS and other health risks associated with breaking down of the tops of insitu bored piles Description This technique involves the removal of the unwanted pile section in one piece, exploiting the physics of crack propagation. Steel reinforcement above the final cut-off level is prevented from bonding with the concrete by fixing isolating sleeves to the bars before the cages are lowered into position (1). When the pile is finally exposed a 51mm diameter hole is drilled horizontally into the concrete at cut-off level to just beyond the centre of the pile (2). A standard hydraulic splitter is inserted and activated (3) and after around 30 seconds the concrete cracks across the desired level. Then an excavator is used to lift off the surplus in a single piece via a lifting eye cast into the top surface (4). Elliot claim that the operation cuts the hand-arm vibration risk by more than 90%. It will work on pile diameters from 300mm to 3m and typically takes around 10 minutes (5), bringing significant productivity and cost benefits. Design action required Actual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer). Main residual health risks One 51mm hole is drilled into the pile with some associated vibration hazards (approx 5 minutes task time). Some MSD hazards may remain in the manoeuvring of the pile top section although this is a crane operation. Note: There are a number of alternative methods addressing this health risk. (link to table) Loughborough University Images courtesy Elliott – www.Elliott-Europe.com

19. Elliott Crack Propagation Courtesy Elliott

20. 2 1 3 4 7 6 5 8 9 D4h Major Building – Pile top break down Occupational Health Innovation Chemical pile break method (Recepieux) Main health issues addressed HAVS and other health risks associated with breaking down of the tops of insitu bored piles Description Recepieux’s technique involves the removal of the unwanted pile section in one piece, exploiting the principle of crack propagation induced using an expanding grout. The steps are as follows: 1 Foam sleeves are fixed over the reinforcement over the length to be removed 2 A series of PVC tubes and cones is assembled 3 The tube and cone assembly is pushed into the wet concrete 4 The tube assembly is checked for level and funnels fixed to the top of the tubes 5 The temperature of the pile concrete is measured (this affects the grout mix choice) 6 The expanding grout is mixed and batched into containers 7 The grout is poured into the tubes via the funnels 8 The grout expands in the cones set at ‘cut-off’ level propagating a horizontal crack through the pile 9 The top unwanted section is removed by crane Design action required Actual choice of technique is usually left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer). Main residual health risks COSHH issues with the grout and increased work required to the wet concrete during pile construction. Some MSD hazards may remain in the maneuvering of the pile top section. Note: There are a number of alternative methods addressing this health risk. (link to table) Note: there are examples of poor use of PPE in these images Loughborough University Images courtesy Recepieux – (http://www.recepieux.com)

21. Traditional insitu bored pile cast approximately 1m above cut-off level Horizontal crack induced at cut-off level by expanding grout inserted through tubes. Recepieux Chemical Crack propagation Courtesy Recepieux

22. Note poor PPE Recepieux Chemical Crack propagation Courtesy Recepieux

23. D4h Major Building – Pile top break down Occupational Health Innovation Hydraulic pile break method (Taets) Main health issues addressed HAVS and other health risks associated with breaking down of the tops of insitu bored piles Description The Taets system from the Netherlands replaces hand-held pneumatic breaking with a large scale hydraulic breaker. The breaker is suspended from an excavator and makes a horizontal fracture in the pile at cut-off level. Each hydraulic cylinder drives a chisel into the concrete producing a horizontal fracture as the breaking force built up this way always seeks the shortest way through the concrete. This stage takes about 25 seconds. The steel chisels do not have to penetrate beyond the reinforcement bars. After the fracture is made, the chisels penetrate further into the concrete (usually 25-40 mm). Due to the shape of the chisel, in combination with the reaction forces on the concrete by the steel reinforcement, the concrete breaks into pieces and can removed without the need for further breaking. Design action required Actual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer). Main residual health risks Slight MSD risk maneuvering breaker although this is a crane / excavator operation. MSD risks disposing of broken concrete – depending on techniques used. Some dust and noise. Note: There are a number of alternative methods addressing this health risk. (link to table)  Loughborough University Images courtesy Taets – (http://www.taets.nl/#B)

24. D4h Major Building – Pile top break down  Loughborough University Images courtesy Taets – (http://www.taets.nl/#B)

25. D4h Major Building – Pile top break down Occupational Health Innovation Hydraulic pile break method (Mantovanibenne) Main health issues addressed HAVS and other health risks associated with breaking down of the tops of insitu bored piles Description The Mantovanibenne system replaces hand-held pneumatic breaking with a large scale hydraulic breaker in a similar way to the Taets system. This system was recently used on Norwich FC’s Carrow Road ground (NTW Civil Engineering / Inmalo). The system can accommodate piles between 350 and 1600mm for both circular and square piles. The team claim significant productivity as well as health and safety benefits (Construction News, 11/09/03 p.20). Design action required Actual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer). Main residual health risks Slight MSD risk maneuvering breaker although this is a crane / excavator operation. MSD risks disposing of broken concrete – depending on techniques used. Some dust and noise. Note: There are a number of alternative methods addressing this health risk. (link to table)  Loughborough University Image courtesy Mantovanibenne

26. D4h Major Building – Pile top break down  Loughborough University Courtesy Mantovanibenne

27. Traditional insitu bored pile cast approximately 1m above cut-off level Hand-held breaking replaced by crane-handled hydraulic breaker. Option 4 – Hydraulic breaker Courtesy Taets

28. D4h Major Building – Pile top break down Occupational Health Innovation Precast sacrificial guide wall (Cementation-Skanska) Main health issues addressed HAVS and other health risks associated with breaking down of the tops of insitu bored piles, along with other pile top hazards Description Contiguous piled walls require more accurate alignment and need a temporary, sacrificial concrete guide wall to be cast before the piling operations through which the auger passes. The Cementation-Skanska system prevents the abortive work of the early guide wall, which in the final permanent state is usually replaced by a concrete capping beam of similar dimensional proportions. The system utilizes pre-cast concrete guidesplaced into position and retained by a non-structural concrete surround. By preventing contamination to the tops of the piles, they can be poured to ‘cut-off’ level in the first place removing the need to break-down the pile tops. Circular voids in the mould allow the piling auger to pass through the mould in the required position. Adjacent voids are protected with circular ‘lids’ to prevent them being filled with concrete or pile arisings. 1 - guide blocks being placed along the line of the wall 2 - auger drilling ‘through’ the block guides 3 - blocks removed after the piling operation and also the shape left by the blocks acting as the formwork for the capping beam. Design action required Actual choice of technique is probably left to the Principal Contractor. However, designers should identify the significant risk and ask the PC for proposals to remove the risk (knowing that there is an answer). Main residual health risks Additional operations involve the placement of the precast guide wall units which may involve some MSD hazards. Note: There are a number of alternative methods addressing this health risk. (link) Loughborough University Images courtesy Cementation Foundations - Skanska

29. Designed for contiguous piling Enables pile to be cast to ‘cut-off’ level Avoids contamination of wet concrete from surrounding ground Avoids need for breaking down pile top. Cementation-Skanska sacrificial guide wall Courtesy Cementation-Skanska and Carillion

30. D4h Major Building – Pile top break down Loughborough University

31. Designer/PS knowledge of pile break innovations Sample size 40 Main primary function – designers (Arch & Eng) Main secondary function – Planning Supervisors

32. D4h Designing for healthy construction The challenge…….. To design-out health risks for construction workers • Are we aware of the innovations? • Do our designs preclude their use? • Do we have mechanisms in place to access expert knowledge? • Are we proactive in encouraging design innovations?.

34. Alistair Gibb Construction Health and Safety There is a better way!