Risk assessment

Risk assessment forms an integral part of the design function when a decision has to be taken between the risk to health and safety and other design considerations.

Risk is defined as the likelihood of potential harm from a hazard being realized. Ahazard includes articles, substances, plant or machines, methods of work, the working environment and other aspects of work environment with the potential to cause harm.
The HSE have provided guidance on the execution of risk assessments in their ‘Five Steps to Risk Assessment’ leaflet. The document is aimed at workplace risks; however it is a useful model for engineers to follow during the design and construction phases of a project. Risk assessment is set out under the following steps:
1. Look for hazards.
2. Decide who might be harmed and how.
3. Evaluate the risks and decide whether the existing precautions are adequate
or whether more should be done.
4. Record your findings.
5. Review your assessment and revise if necessary.

Engineers should also refer to the policy and procedures set out within their own company safety management system relating to the requirements of CDM and the Management Regulations and the undertaking of risk assessments.
It is important to remember that having identified the hazards and those at risk (step 1 and 2) it is necessary to assess the level of risk (step 3) in order to decide on the order of significance and the preventive action needed. The approach here may be qualitative, based on subjective judgements, or quantitative using numerical estimates of risk based on probability and severity derived from empirical data. In certain industries, particularly where high risks are involved (e.g. chemical and nuclear industries), the quantitative approach is necessary in order to comply with legal or licensing requirements and this requires a more complex risk assessment methodology driven by statute.
Many people think that the risk assessment process ends when the risks have been assessed or ranked but this is incorrect. Giving risk a ‘number’ or rank is only the first phase in the management of risk and appropriate measures then need to be identified in order to eliminate or reduce the risks to as low a level as is reasonably practicable.
Reasonably practicable
CDM Regulation 13(3) requires the design to include matters ‘… to the extent that it is reasonable to expect the designer to address them at the time the design is prepared and to the extent that it is otherwise reasonably practicable to do so.’
The term ‘reasonable’ or ‘reasonably practicable’ is used in many of the post 1974 Act legislation and its meaning can be obtained by reference to common law judgements:
‘Reasonably practicable’ (implies) that a computation must be made…in which the quantum of risk is placed on one scale and the sacrifice…for averting the risk (whether in money, time or trouble) is placed on the other….
Asquith AF; Edwards v National Coal Board (1949)
The HSE provide guidance sheets and many other publications to assist the designer with ensuring the requirements of Regulation 13 are satisfied.
CIRIA1 report R166 is also recognized as a valuable publication intended to assist designers of construction projects to produce schemes that are safer to build and maintain. It provides essential guidance on the identification of hazards in relation to the health and safety of construction workers and those affected by construction work. It shows ways in which hazards can be avoided, reduced or controlled, together with options designers may be able to employ to comply with the CDM Regulations.