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Teresa Budworth, Chief Executive of the health, safety and environmental examinations body NEBOSH, looks at three of the key hazards in construction – working at height, excavation work and the movement of vehicles.
Construction work is dangerous. According to the International Labour Organisation (ILO), almost 20% of all workplace deaths throughout the world occur in the construction industry.
ILO estimates reveal that around 60,000 construction workers die every year worldwide. That’s around one death every ten minutes. Hundreds of thousands of construction workers also suffer serious injuries and ill health.
By far the main causes of death and injury are falls, crushes and impacts. This means that working at height, excavation work and the movement of vehicles and plant are three of the key areas to control in any construction environment.
Working at height
Working at height leads to more deaths and serious injuries in construction than any other activity. To understand how to control the hazards that work at height presents, it’s important to know what is meant by ‘height’. A question that is often raised by those first learning to carry out site safety inspections is: “How high does working at height mean? Is it one metre, five metres or 10 metres?”
The answer, of course, is that it could be any of these – it can be higher, or it can even be lower. What is important is to recognise any situation where there is a need to control a risk of falling that could lead to injury. Quite simply, anything from using a small stepladder to repair some brickwork, to moving materials next to a large excavation area could be considered ‘working at height’.
So a safety inspection to identify working at height hazards must focus on the risks of falling. But what about subsequent control measures? How should these be applied?
There is a three stage hierarchy to controlling the risks of working at height. As David Burt of health, safety and environmental specialists PMB Management Ltd explains, the first is simply to avoid working at height whenever possible. He said: “On any construction site, you occasionally see tasks being carried out at height that you could reasonably expect to be carried out at ground level.
For example, putting component parts together, while working at height, instead of assembling these first at ground level.”
Of course it’s not always possible to carry out construction tasks without there being a risk of falling. Here, the second part of the safety hierarchy applies – taking suitable precautions to prevent someone from falling.
To begin with, serious consideration must be given to how the works are to be carried out at the planning stage. For example, the right working platform should be used for each and every task. Ladders are good for access and light work of a short duration. When carrying out tasks such as drilling or fixing items, however, a working platform is more appropriate. Careful planning helps to ensure that the right equipment is available and used whenever someone is working at height.
“Simple precautions to prevent someone falling include the use of toe boards and guardrails on scaffolding, or making sure the brakes are applied correctly when using a mobile elevated work platform,” said Mr Burt.
“It should be remembered that working at height can also mean falling into an excavation or chamber. As a result of this, toe boards and guardrails should be used to protect these areas too.”
The third stage in the hierarchy of control is to minimise the distance and consequences of a fall. In practice, this could mean the use of safety nets, large airbags or safety harnesses. As Mr Burt explained, however, where such precautions are used, there is an additional need to ensure that a suitable and sufficient rescue plan has been developed.
“This is necessary so that events like orthostatic shock – a medical term for the body’s inability to cope with prolonged periods of immobility in a vertical position – don’t occur. This condition affects everybody irrespective of gender, fitness or body shape.
“Before any work at height is to be carried out a competent manager or supervisor must identify all the reasonably foreseeable hazards and ensure that adequate and appropriate control measures are implemented.”
As with all health and safety training, supervision and suitable instruction are essential. Method statements, or safe systems of work should be used. These should make anyone tasked with construction activities aware of the risks and provide step by step guidance on how to carry out the work safely. Method statements are particularly important when it comes to the use of contractors and sub-contractors, who may not have received the same level of induction or health and safety training as employees.
Even when the above measures have been implemented, there is still the need to ensure that working at height is properly supervised and managed by competent persons.
One final issue to consider when tackling working at height issues is the risk of falling objects. When it comes to construction materials, tools and equipment, no more than is necessary should ever be stored at height. Head protection in the form of hard hats should be worn at all times by all persons on construction sites and safety netting should be used. The risk from falling objects to members of the public should also be properly assessed and controlled.
Excavation work
By far the greatest risk associated with excavation work is the danger of collapse. This is not just the case with deep excavation work either; many incidents leading to death and injury occur in shallow workings.
In the UK earlier this year, Cotswold Geotechnical Holdings became the first company to be convicted of the new offence of corporate manslaughter. Alex Wright was 27 years old when he died on September 5, 2008. He was a geologist for Cotswold Geotechnical Holdings and was investigating soil conditions in a deep trench on a development plot when it collapsed and killed him.
Other hazards associated with excavation work include people, materials and vehicles falling into the works, influx of water leading to drowning or entrapment in mud, stability of nearby structures, underground services such as electrical cables and hazardous substances, fumes, lack of oxygen or other health hazards.
As with working at height, a site safety inspection is essential to identify the hazards present, assess the risks and then take relevant precautions and instigate control measures.
To assist, the following checklist can be used in both the planning and execution of excavation works:
1. Pre-start excavation checks
• Check that a risk assessment has been carried out and that hazards associated with excavations are included within the health and safety plan
• For purposes of excavation, no ground should be considered good or safe until it has been investigated – review Site Investigation Reports if they are available
• Prevent all access to the excavation by unauthorised persons, especially children
• Check the soil types and decide which type of support work is required in consultation with a competent engineer
• Check whether the excavation will affect adjoining roads, buildings or other structures, such as scaffolds
• Determine the position of all services, especially buried services, and ensure that they are adequately marked, supported or disconnected as necessary – refer to Utility drawings and carryout a CAT scan before starting any work • Always seek advice before excavating below existing foundations of adjacent or adjoining buildings – it may be necessary to provide shoring, e.g. raking
• Provide an adequate supply of material for support work, along with barriers and correct traffic notices
• Make provision for any side support system to stand proud of the existing ground levels – this prevents any loose material from falling into the excavation
• Check the need for, and provision of, adequate lighting. Also check that adequate and sufficient ladders have been provided for safe access to the excavation and that sufficient ropes for securing these items are to hand
• Determine the methods of excavating before starting work, and the method by which it is intended to install and remove any support work. Also determine the position of bridges, temporary roads and spoil heaps
• Plan traffic routes to keep heavy plant and vehicles away from excavations as far as is possible, except where they must approach the excavation for tipping and lifting activities
• Plan the safe backfilling of the excavation, using suitable materials
2. Safety checklist while digging, working in, or reinstating an excavation
• Ensure that only sound support material is used and that approved and safe methods are adopted for the installation of support work in excavations. A competent person should be in attendance at all times
• Ensure that all working surfaces are safe. Install timbering as soon as the excavation sides are trimmed – this should be done from a work cage, from ground level, or from inside existing timbering
• Ensure that all support work is secure and that props and wedges are tight and properly maintained. Check for signs of overstress in support work, any damage that may have been caused by plant and, when timber is used, make long term checks for disease and defects, e.g. dry rot or shakes
• Check for any water or soil which may be seeping through support?work and for signs of the earth peeling or cracking at unsupported faces
• Check that there are adequate ladders, that they are maintained, secured and used correctly
• When pumping, ensure that there are adequate sumps and that soil is not being drawn from behind support work
• Check for hazardous atmospheres
• Ensure that spoil heaps and other materials are kept back from the edges of the excavation and that there are adequate barriers, notices and warning lights
• Check that the edges of excavations are provided with top and mid guardrails at all places where there is a danger of persons falling a distance that is likely to cause personal injury
• Check that any bridges and gangways are fitted with guardrails and toe boards
• Ensure that stops for dumpers and tipping lorries are well anchored and that all passing traffic is kept well back from the edge of the excavation
• Ensure that the correct method of withdrawing support work is used – if for any reason it is considered unsafe to remove it, leave it in
• Ensure there is adequate separation between working plant and people
• Ensure that appropriate protective clothing and protective equipment are being used and that people wear suitable ear defenders when piling or other noisy activities are taking place
• Ensure that machine operators have the best possible vision of the work which is in progress and that services are marked, protected and adequately supported when exposed in excavations
• Ensure that any backfilling is carried out correctly and in a planned sequence, and maintained
• Ensure that each excavation is inspected by a competent person before it is first entered; at the start of each shift; after any accidental fall of rock, earth or other material; after any event likely to have affected the strength or stability of the excavation
• Also ensure that a proper record of all inspections is made and signed by a competent person. Remember that records of inspections may be kept on computer or in another electronic form, so long as it is possible to immediately produce a hard copy on request
Ensure that the written report, or a copy, is provided to the person on whose behalf the inspection was made within 24 hours
Movement of vehicles and plant
Workplace transport is a significant hazard on construction sites. Cranes, dumpers, forklift trucks, excavators and many other types of vehicle provide serious risk of accidents from overturn and collisions with pedestrians or plant/equipment. Even employee car parking areas can present risks if not managed correctly.
As well as safety risks, workplace transport brings with it a whole host of health issues such as noise, vibration?and breathing in fumes from exhausts. According to Nick Higginson, Managing Director of Phoenix Health and Safety, it is useful when assessing risks and deciding on control measures for workplace transport on construction sites, to split the issues into three separate areas:
1. The workplace 2. The vehicle 3. The driver
“The workplace should be made as safe as possible, which means segregating workers from vehicles wherever you can, ideally by means of physical barriers,” said Mr Higginson, adding:
“A traffic plan should be in place that clearly designates where vehicles may be operating and who has right of way. The need for reversing vehicles should be minimised as much as possible, which can be achieved by implementing one way systems, or providing turning places for large vehicles. “Where pedestrian crossing routes are needed, they should be clearly marked. Adequate signage should be provided to instruct drivers and pedestrians, for example speed limits, give way, no entry and so on.”
Vehicles themselves must be suitable for the intended job, and be provided with all required safety features. Correct tyres should be on the vehicle, with good treads, and they should be properly inflated to the correct pressure.
Measures must be taken to protect drivers in the event of overturn, such as the provision of seatbelts and roll over protection structures (ROPS). Falling object protection structures (FOPS) should be provided on vehicles that are at risk from falling objects, for example forklift trucks or vehicles used in demolition activities.
Vehicles should be provided with appropriate mirrors to aid visibility – in some cases larger mirrors and/or CCTV may need to be provided in vehicle cabs, especially in large vehicles.
Visual and audible warning devices should be provided; for example, flashing lights and reversing alarms or sounders. All vehicles should be subject to a planned maintenance schedule that complies with the recommendations of the manufacturer. In addition, regular daily and weekly checks should be carried out by operators to check the condition of tyres, brakes, windscreens or lifting mechanisms.
These checks should be recorded and any defects acted upon immediately.
Drivers should be suitable for the job, physically fit and competent to drive the vehicle. Medical checks may be necessary. “All drivers should be appropriately trained, which normally means attending a course, passing a test and obtaining a licence for the vehicle,” Mr Higginson said. “Drivers need adequate experience and a mature attitude. Ongoing monitoring and supervision is then required to ensure that the vehicle continues to be driven safely.”
All workers and drivers also ought to receive site induction training that includes topics such as site rules, parking areas and speed limits Mr Higginson said. ILO code of practice Although around 20 years old now, one of the most important documents available to anyone responsible for health and safety in construction is the ILO Code of Practice ‘Safety and Health in Construction’. This is available as a free download from the ILO website (www.ilo.org).
The code provides practical guidance on legal, administrative, technical and educational issues in construction safety, wherever in the world it is to be applied. The aim of the document is to prevent accidents and diseases and harmful effects on the health of workers.
It also looks at appropriate design and implementation of construction projects, providing means of analysing from the point of view of safety, health and working conditions, construction processes, activities, technologies and operations, and of taking appropriate measures of planning, control and enforcement.
Working at height, excavation work and transport are all covered in detail in the document, as well as many other hazards.
Conclusion
Thorough planning, site inspections and rigorous controls and procedures can turn dangerous construction sites into places that are safe for employees, contractors and others. I believe we owe it to the 60,000 people who are killed each year on construction sites to ensure the kind of standards promoted in the ILO code are implemented everywhere.
Author
Teresa Budworth is a Chartered Safety and Health Practitioner, Fellow of IOSH and a Chartered Director. During a 30 year career in health and safety she has specialised in safety consultancy, working with a number of boards of directors on implementing safety governance within large and diverse organisations.
Her work on competence, education and training culminated in her appointment as Chief Executive of NEBOSH, the National Examination Board in Occupational Safety and Health, in 2006.
T: +44 (0) 1162 634700 W: www.nebosh.org.uk E: [email protected]
NEBOSH news
A reception was recently held at the British Embassy in Bahrain Embassy to mark launch of NEBOSH exam in Arabic. It is hoped that the new Arabic qualifications will further support businesses both in Bahrain and in the rest of the Middle East and North Africa in promoting health, safety and environmental improvements.
NEBOSH exams are taken in more than 91 countries throughout the world and 41% of the exams taken outside of the UK are held in Middle Eastern countries.
NEBOSH was formed in 1979 and is an independent examining board and awarding body with charitable status. NEBOSH offers a comprehensive range of globally-recognised, vocationally-related qualifications designed to meet the health, safety, environmental and risk management needs of all places of work in both the private and public sectors.
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Published: 10th Jan 2012 in Health and Safety Middle East
