Residual Risk in Health and Safety

Everyone working in the health and safety sector comes across risks on a daily basis, some more significant and more likely to cause harm than others. Employers are required to manage these risks with a risk assessment, but what happens when risks cannot be eliminated completely? What constitutes an acceptable level of residual risk? In this article, we’ll outline what residual risk in health and safety means, provide you with some examples of residual risks and explain how to calculate residual risk in your business.

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What is Residual Risk in Health and Safety?

In health and safety, a risk is defined as the likelihood and severity of something causing harm to a person. All employers are required to manage the level of risk in their workplace under the Management of Health and Safety at Work Regulations 1999. Employers must carry out a risk assessment that identifies hazards and prompts the implementation of control measures that reduce the risks to as low as reasonably practicable (ALARP).

Residual risk in health and safety is the level of risk that remains, even after a thorough risk assessment has been carried out and control measures have been applied. Residual risk will always exist as no one is expected or able to eliminate all risks in the workplace completely. The aim is always to reduce the risks to ALARP.

Residual risk may exist inherently because of the task at hand, it may be that there are no suitable control measures that can reduce the risk, it could be that by reducing the risk you are inadvertently introducing other hazards or it could be that it’s ‘disproportionate’ to put control measures in place.

Ideally, all residual risks will be low and insignificant but, if the residual risk is identified as being severe and cannot be reduced to ALARP, then this must be recorded and communicated to anyone involved in the work activity. Employers have a legal duty to protect the health, safety and wellbeing of those in their workplace, so implementing a safe system of work may be the best approach in these situations.

Residual Risk vs Inherent Risk

A residual risk is the level of risk that still exists after controls have been put in place to reduce it. It’s a risk that has been reduced and controlled to some degree by a thoughtful and thorough risk assessment.

An inherent risk is the level of risk that exists before any controls have been put in place to reduce it. It’s a risk that’s uncontrolled and no attempt has been made to reduce its likelihood or severity. All tasks carry an inherent risk, whether it’s significant or insignificant.

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Examples of Residual Risk

Some examples of common residual risks in health and safety include:

• Falls from height – the use of ladders to complete a task may be unavoidable in your business, so how can you reduce the residual risk of falls? Consider if alternate access equipment is more suitable, such as a mobile working platform, whether the duration of the task can be reduced and how often the ladder is inspected for safety.
• Manual handling injuries – lifting, pushing and carrying often can’t be avoided, whether you work in a warehouse or an office. Reduce the residual risks from manual handling by making sure people don’t lift more than they can manage, that routes are clear and that workers are properly trained in manual handling methods.
• Work in confined spaces – many roles in the health and safety sector require workers to carry out tasks in small spaces, and this cannot be avoided so the residual risk cannot be removed. To reduce the risk of harm to ALARP, ensure you have a suitable permit to work and that the area is inspected by a suitable competent person before work begins.
• Electric shocks and burns – contact with electricity may occur when any sort of maintenance or building work is carried out, even if you’ve carried out a full inspection and risk assessment beforehand. To reduce the chances of accidental electrical burns or shocks, always follow isolation procedures before starting work.
• Exposure to hazardous substances – many tasks involve using chemicals and the job cannot be done without them. Alternatively, you may be at risk of coming across other hazardous substances, like asbestos, in the course of your work. To reduce the chance of harm, always follow COSHH procedures and wear appropriate protective clothing.

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How to Calculate Residual Risk

Residual risk can be calculated using the following formula. The higher the number calculated, the higher the residual risk.

Likelihood x Severity = Residual Risk

To do this calculation, you can give values to Likelihood and Severity. For example:

• Likelihood can range from impossible (1) or unlikely (2) to occasional (3), likely (4) and almost certain (5).
• Severity can be measured on a scale from insignificant (1) and minor (2), to moderate injury (3), serious injury (4) or fatal (5).

If your calculation gives you a high number for the Residual Risk (over 6), then it means the level of risk is still high and would not normally be acceptable as a residual risk. Instead, more control measures are required to reduce the value.

If your calculation gives you a low number for the Residual Risk (under 6), then it means the level of risk is low and it would be an acceptable residual risk value.

Keep in mind that this calculation does not give you a definitive answer about whether a residual risk is acceptable or not. The acceptable level of residual risk is based on the organisation’s judgement of the situation.

To make a judgement on what constitutes an acceptable residual risk, the employer or competent person needs to assess the risk and determine whether they believe it’s being adequately controlled. Do the benefits outweigh the consequences? If yes, then the work activity can go ahead as the residual risk is acceptable. If they determine that the risk is not being adequately controlled to ALARP, then the residual risk is unacceptable and further control measures are needed.

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Residual risk in health and safety is the remaining risk that exists after control measures have been implemented. No workplace can entirely eliminate risks, so employers must aim to reduce risks to as low as reasonably practicable (ALARP) and assess whether the benefits of an activity outweigh the potential harm. If residual risk remains high, then additional measures are needed to ensure workplace safety and compliance with regulations.

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Further Resources:

• Online Health & Safety Courses
• What is ISO 31000 – Risk Management?
• What is a Competent Person?