Last reviewed 28 April 2020
One of the main causes of deaths and injuries at work each year is falling from height, particularly through or from roofs. Mike Sopp advises on the steps to planning roof work safely.
Falls from height typically occur when people fall through fragile roofing materials or from unprotected edges.
Numerous prosecutions have taken place, many of which indicate that the main causes of these incidents are a lack of adequate planning by those responsible for the roof work and consequent failings in precautions, supervision and training.
Planning is therefore essential for any work on roofs but as the Health and Safety Executive (HSE) states, “employers and those in control must first assess the risks”.
Hazards and roof work
There may be many reasons for work to be carried out on or near roofs. From the initial construction through the necessary maintenance, cleaning, repairs, refurbishment of roof elements and any plant or equipment located on the roof to the final stripping/dismantling of a roof.
According to the HSE, “working on roofs is a high-risk activity because it involves working at height”. Accident statistics identify that falls from height at work are the biggest single cause of fatal workplace injuries, and the second biggest cause of major injuries.
The single biggest immediate cause of deaths is falls through fragile materials, such as roof lights and asbestos cement roofing sheets.
However, it is recognised that many of the accidents involving falls from height have as a contributory factor a lack of capability and/or competency both in undertaking the work activities and in the planning/organisational aspects of the roof work.
The lack of a suitable and sufficient risk assessment is also often cited in subsequent prosecutions undertaken by the HSE.
The Work at Height Regulations 2005 (WAH) require employers to ensure that any work that is taking place at height is properly planned, appropriately supervised and “carried out in a manner which is so far as is reasonably practicable safe”. The regulations also require the dutyholder to:
avoid work at height where they can
use work equipment to prevent falls when work at height cannot be avoided
when the risk of falls cannot be eliminated, use work equipment to minimise the distance and consequences of any fall.
However, it is almost inevitable that some form of work will have to take place on roofs and as such, it is essential that planning and assessing of any roof work be undertaken. Regulation 6 of WAH sets out a hierarchy of control for determining how to work at height safely. The hierarchy has to be followed systematically and only when one level is not reasonably practicable may the next level be considered.
Where roof work cannot be avoided under WAH, the dutyholder must ensure that:
all roof work is properly planned and organised
those involved in planning and carrying out the work are competent
the risks from the work are assessed
appropriate work equipment is selected, used, maintained and inspected
the risks from fragile surfaces are properly controlled
the risks from falling objects are properly controlled
emergencies and rescue are planned for (for example, if a fire occurs).
The regulations themselves do not contain a specific requirement to carry out a risk assessment but rather state that “every employer shall take account of a risk assessment under regulation 3 of the Management of Health and Safety Regulations 1999”.
The factors to be considered in such a risk assessment will include the following:
the work activity (ie the proposed roof work)
the equipment to be used (both for access and egress purposes, and in the actual work activity)
the duration of the work
the location of the roof (to determine the presence of hazards such as overhead power cables)
the work environment (including weather conditions, lighting, space, etc)
the type, condition and stability of the roof (including fragility, sloping, flat or industrial roof)
the physical capabilities and competency of the workers
emergency procedures required in the event of an incident or accident.
Completion of a risk assessment should then enable an appropriate method statement to be produced for the work to be undertaken that according to the HSE should “make sure that risks are recognised and assessed, and the appropriate control measures specified”.
The method statement should be “job specific”, and be fully understood and agreed by all parties involved in the roof work. Both HSG33 Health and Safety in Roof Work and guidance from the Advisory Committee for Roofsafety (ACR) contain useful information as to the content of a method statement.
As mentioned above, fragile surfaces on roofs is a major contributor to accidents occurring. WAH contain specific requirements in relation to “fragile surfaces” which is given the definition of “a surface which would be liable to fail if any reasonably foreseeable loading were to be applied to it”.
HSG33 states that “any work on fragile roofs, however trivial it may seem, should be carefully assessed, planned and supervised” and that “all roofs should be treated as fragile until a competent person has confirmed they are not”.
Therefore, a key element of the risk assessment process and consequent planning is determining if the roof is deemed to be fragile. This should be completed by a competent person as detailed below.
There is now a widely recognised test to show non-fragility for a roofing assembly that has been drawn up by the ACR and published in their “Red Book”, and also detailed in HSG33.
Although non-fragile roofs are becoming commonplace through building construction standards, HSG33 notes that “there is a serious risk that roof workers become complacent and do not recognise that a non-fragile roof will, at some point in time, become fragile”.
Therefore as part of the assessment process, the factors that could cause fragility should be addressed including:
general deterioration of the roof due to ageing, neglect and lack of maintenance
corrosion of metal clad roofs and fixings
quality of the original installation
selection of original material, fixings and washers
subsequent impact and thermal damage
deterioration of the supporting structure, sheeting and fixings from below due to processes within the building and other causes
damage from rain and storm water leading to random areas of weakness.
Working on a roof can be an extremely hazardous activity. The HSE’s accident statistics show that many accidents happen because the people carrying out the work are not trained or competent to do so.
WAH require employers to ensure that “no person engages in any activity, including organisation, planning and supervision, in relation to work at height or work equipment for use in such work unless they are competent to do so”.
With WAH stipulating that competency is required not just in operational activities but also in planning and organising activities as well, the risk assessment needs to determine the competency required not only to undertake the work but also to plan and supervise it.
The ACR “Black Book” makes recommendations on competency for those who commission, plan, manage, supervise and undertake activities.
For those who commission roof work, the ACR recommends that they “should have the ability to establish and operate permit to work systems”.
For those who organise and plan roof work, the Black Book recommends that a person has:
knowledge of which health and safety legislation is applicable to roof work and how it should be applied to the task in hand
understanding of the hazards associated with the type of roof or system
the ability to carry out and implement comprehensive risk assessments, to deal with associated hazards
the ability and authority to select the most appropriate working equipment for the task, regardless of financial constraints
understanding of method statements and what needs to be included within them.
Similar competency criteria are recommended for those who manage roof work but the Black Book makes additional recommendations including those who manage the work to have “knowledge of the correct hierarchy of fall protection implicit within the regulations covering work at height”.
It is also recommended that those who supervise have the competency to work at height but must also have the following.
Ability to identify and pre-empt a dangerous situation developing, and how to intervene and stop the situation developing.
Ability to recognise dangerous working practises and workers.
Authority to stop own and others work until a safe environment has been created.
Clearly, those who physically undertake roof work must have a level of competency. HSG33 states that “roof workers need appropriate knowledge, skills and experience to carry out roof work safely and competently”.
It is worth noting that competency also includes roof workers recognising “their limitations and take appropriate action to prevent harm to those carrying out the roof work or those affected by the work”.
Another specific area addressed is the ability to “assess the non-fragility of a roof”. In respect of this, competency criteria are deemed to be as follows:
sufficient knowledge of the mechanical and physical properties of the materials and assemblies involved
practical experience of correct installation of the product, usage, behaviour and failure in service
understanding of the techniques to gain access to the roof.
HSG33 Health and Safety in Roof Work, HSE
The Black Book. Guidance Note for Competence and General Fitness Requirements to Work on Roofs, Advisory Committee for Roofsafety
The Orange Book. Recommended Practice for Work on Profiled Sheeted Roofs, Advisory Committee for Roofsafety
The Green Book. Safe Working on Fragile Roofs or Roofs with Fragile Elements, Advisory Committee for Roofsafety
The Red Book. Test for Non-fragility of Large Element Roofing Assemblies, Advisory Committee for Roofsafety