More on risk evaluation

Having identified the hazards, who might be harmed and how it is necessary to determine whether they are effectively controlled with whatever risk controls/precautions are currently in place. If not, additional controls will need to be identified and implemented so that effective control of the hazard can be achieved.

Legally, there is a requirement to do all that is â€œreasonably practicable” to protect people from harm.  This requires the degree of risk (likelihood x severity) of a particular activity or environment to be balanced against the costs (time, trouble and physical difficulty) of taking measures to avoid the risk.

The greater the risk, the more likely it is that it will be reasonable to go to very substantial expense, trouble and invention to reduce it.

If the consequences and the extent of a risk are small, the same substantial expense would be considered disproportionate to the risk and it would be unreasonable to have to incur them to address a small risk.

The size and financial position of the employer are not taken into account in consideration of what is ‘reasonably practicable’.

The first part of the process of evaluating the risk is considering both the likelihood of harm occurring, given the current controls in place, and the seriousness/severity of the harm should it occur. This enables risks to be compared and priorities to be established.

Factors affecting likelihood

  • the number of people doing the task,
  • how often they do it (frequency)
  • for how long (duration)
  • work pressures, such as productivity bonuses
  • the competence of the workers
  • whether current risk controls are adequate
  • environmental conditions, such as the weather

Factors affecting severity

  • potential for harm (toxicity, dimensions, weight, distance etc.)
  • potential magnitude of the harm
  • history of the harm
  • potential population at risk

When it comes to severity of harm, it is essential to consider the properties of the hazard, for example, some substances can be classified as toxic, corrosive, harmful etc. and what sort of harm could result from exposure to a hazard, for example: whether exposure could cause:

  • Serious effects or death, either immediate or delayed, occurring from single exposures to the substances, i.e. the effects of acute exposure
  • Adverse effects or death resulting from repeated, even low level, exposures over a long period of time, i.e. the chronic exposures
  • Both long-term and short-term effects, i.e. the effect of acute and chronic exposure

The second part of the process is to review controls already in place against recognised standards of good practice. This benchmarking exercise will determine if there is more that needs to be done. Having completed a risk assessment and having taken account of existing controls, the organisation should be able to determine whether existing controls are adequate or need improving, or if new controls are required.

Improving health and safety need not be expensive, e.g. placing a mirror on a dangerous blind corner to help prevent vehicle accidents is a low-cost precaution considering the risks, particularly when compared to the cost of the accident it may prevent.

Priorities should be based upon such considerations as the level of the initial risk, the numbers of people affected, legal requirements, the level of residual risk after implementing controls, the cost of control, the amount of reliance on human behaviour, the consequences if the control measure fails and ongoing maintenance requirements.

Once the controls have been determined the organisation can prioritise its actions to implement them. In the prioritisation of actions, the organisation should consider the potential for risk reduction of the planned controls. In most cases it is preferable that actions addressing a high-risk activity or offering a substantial reduction of risk take priority over actions that have only limited risk reduction benefit.

If there are a lot of improvements that need to be made, an action plan should be developed to prioritise them so that they can be dealt with effectively.

Priorities are generally determined by the risk ratings (the outcomes of the risk evaluation as discussed earlier) i.e. those that are considered ‘high risk’ based on the likelihood and severity of harm occurring should be considered as highest priority. Other factors to be considered might include:

  • Whether the risk arises from a breach of legislation
  • Enforcement action (e.g. the service of an Improvement Notice)
  • Reasonable practicability, i.e. the cost of a solution that is proportionate to the risk
  • Supply chain pressure, i.e. it is a requirement for doing business with a customer
  • Exposure of vulnerable people, e.g. children, young people or disabled
  • Affecting the public
  • Other effects on business reputation

A good action plan might include:

  • a few ‘quick wins’ – cheap or easy improvements that can be done quickly, perhaps as temporary solutions until more reliable controls are in place
  • long-term solutions to those risks with the worst potential consequences, especially personal injury or ill-health
  • arrangements for training employees on the main risks that remain and the corresponding controls
  • arrangements for monitoring to ensure that the control measures stay in place
  • clear responsibilities for leading on individual actions
  • target dates for completion

In some cases, it is necessary to modify work activities until risk controls are in place or apply temporary risk controls until more effective actions are completed. For example, the use of hearing protection as an interim measure until the source of noise can be eliminated, or the work activity segregated to reduce the noise exposure. Temporary controls should not be regarded as a long‑term substitute for more effective risk control measures.

Authoritative sources of good practice are prescriptive legislation and Approved Codes of Practice and guidance produced by Government and HSE inspectors. Other sources include standards produced by standard-making organisations and guidance agreed by a body representing an industrial or occupational sector, provided the guidance has gained general acceptance.

Legal requirements, voluntary standards and codes of practice can specify appropriate controls for specific hazards. In some cases, controls will need to be capable of attaining “as low as reasonably practicable” (ALARP) levels of risk.

Where established industry practices result in high levels of health and safety, risk assessment should not be used to justify reducing current control measures.

The organisation should conduct ongoing monitoring to ensure that the adequacy of the controls is being maintained.

Employers are required to do all that is “reasonably practicable” to protect the health and safety of their employees and others at work.

Determining whether a control measure is “reasonably practicable” requires a balancing of the costs of dealing with the risk (money, time, effort) against the risk of injury (likelihood x severity). The greater the risk the greater the efforts expected to control the risk. If there is gross disproportion between the two, i.e. significant resources are required for minimal risk improvement then it may be argued that the control is not reasonably practicable.

The objective is to manage risks to a tolerable level which is one that people are willing to live with because it delivers certain benefits, and because there is confidence that the risk is being properly controlled. The term “residual risk” is often used to describe the risk that remains after controls have been implemented.

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