Designing for Health and Safety
CDM (GB) Knowledge Base
A designer is any person who makes a design decision about a structure, including materials, equipment, colours, positions, routes, etc. Designers can be just about anyone by default including the client and designers who are not based in Great Britain, so please ensure you understand who a designer can be by reading the relevant section. CDM regulations 9 and 10 make it incumbent upon designers to give due consideration to health and safety in their designs. The regulations require the 'principles of prevention' to be applied by all persons involved in the project, including the designers. This can be achieved by reference to the hierarchy of risk control during the design process. Before this technique can be used it is necessary for the designer to appreciate the principal hazard areas associated with the construction, maintenance, repair, testing, cleaning, etc. so that, when each design element is examined in turn, the potential hazards can be recognised and the hierarchy of risk control applied.
In assessing these principal hazards it is necessary to appreciate the potential severity of the possible harm arising from the hazard. This may be visualised by categorising the hazards and risks in terms of the severity of harm and the likelihood this harm will occur. Thus a fatality or a major illness or injury causing long term disability can be categorised as 'High' severity, an illness or injury causing short term disability as 'Medium' severity and other illnesses or injuries as 'Low' severity. A selection of the principal hazards to be taken into account during each element of the design are:
- Falls from height. Typically these are from ladders, scaffolding, fragile roofs, roof edges or holes in roofs, structural steelwork, temporary work platforms and other parts of floors or surfaces not listed above.
- Trapped by something collapsing or overturning. Typically these are buildings or structures or parts of these, earth or rocks e.g. trench collapse, plant including lifting machinery, collapse of scaffolding and vehicles falling from supports or overturning.
- Struck by moving vehicle. This could be a bulldozer, excavator, private vehicle, road tanker, trailer and others.
- Contact with electricity or an electrical discharge. Caused by domestic type equipment, hand tools or hand lamps, contact with, or close proximity to overhead electric cables or electric cables underground.
- Struck by falling / flying objects. Objects falling from height, falling into excavations or from vehicles.
- Contact with moving machinery. Conveyor belt and hoist. Contact between vehicles or plant and pedestrians.
- Exposure to hot or harmful substance. Substances covered by COSHH and others.
In addition to the above, work related ill-health must be appreciated when examining the design. The principal health hazards associated with the construction industry are asbestos, musculoskeletal injury, respiratory disorders, skin disease, noise, vibration, ionising radiations, lead and compressed air.
Hierarchy of Hazard and Risk Control
- Each element of the design should be examined to identify potential hazards and risks during construction and the life of the building until it is demolished when the process starts again. Once this is done:
- Alter the design to eliminate the hazards and therefore the risks or, if this is not possible:
- Manage the hazards and risks at source e.g. design of items to be lifted to include lifting attachments.
- Priority should be given to measures which will protect generally e.g. design a one way system for delivery vehicles and a separate pedestrian access route. Only after these have been examined should:
- Personal protection of individuals be considered e.g. respirators, safety harnesses etc.
- Provide information about the risks that remain and any assumptions made regarding the methods of work to be adopted to the persons/organisations who need to manage and control these risks.
Reference should also be made to the HSE 'RAG Lists' and other guidance available.
- For further help, see the Hazard Related Topics