Does my business legally need a Legionella Risk Assessment?

If you are an employer or responsible for premises with a water system, you have a legal responsibility to assess and manage the risk of exposure to Legionella bacteria.

This applies to a wide range of workplaces and commercial premises, including offices, factories, warehouses, hotels, schools, care homes, healthcare premises and other buildings where people could be exposed to contaminated water droplets.

The Health and Safety Executive (HSE) states that employers and people in control of premises must identify and assess sources of Legionella risk, manage any risks identified, prevent or control exposure and maintain appropriate records.

What does the law actually require?

The legal requirement is not simply to purchase a document called a "Legionella Risk Assessment".

The responsibility is to identify and assess the risk from Legionella and take appropriate action to control it.

HSE guidance explains that the risk assessment should consider the water systems within the premises and whether conditions exist that could allow Legionella bacteria to grow and spread.

Factors that should be considered include:

• Water temperatures between 20°C and 45°C

• Stored or recirculated water

• Stagnant or infrequently used outlets

• Rust, sludge, scale, organic matter or biofilms

• Showers or other outlets capable of producing aerosols

• Cooling systems

• The vulnerability of people who may be exposed

Not every building will have the same level of risk.

A small office with a simple water system may have a relatively low risk, while a care home, hotel or premises with complex water systems may require much more detailed controls.

Do all businesses need a written Legionella Risk Assessment?

HSE says that all water systems require a risk assessment, but the level of action required should be proportionate to the risk.

For example, an assessment could conclude that a simple water system presents a low risk and that existing controls are adequate.

That does not mean the assessment was unnecessary. The assessment is what establishes the level of risk and determines what controls, if any, are required.

Who is responsible for the assessment?

The responsibility normally falls to the employer or person in control of the premises.

This is sometimes referred to as the dutyholder.

The dutyholder must ensure that the person carrying out the assessment has sufficient competence, knowledge and experience.

A Legionella Risk Assessment can be completed internally where someone has the necessary competence. Alternatively, a competent specialist can be appointed to carry it out.

Does every business need Legionella testing?

No.

A Legionella Risk Assessment and Legionella water testing are not the same thing.

HSE explains that microbiological monitoring is not normally required for standard enclosed hot and cold water systems. Testing may be appropriate in particular circumstances, such as where there is doubt about the effectiveness of the control regime.

The need for testing should therefore be determined by the risk assessment rather than automatically carried out simply because a business has a water system.

How often should a Legionella Risk Assessment be reviewed?

There is no universal rule that every business must have its assessment replaced every 12 months.

Instead, the assessment should be reviewed periodically and whenever there is reason to believe that it may no longer be valid.

For example, a review may be necessary following:

• Changes to the water system

• Building alterations

• Changes in occupancy

• Extended periods of closure

• Installation or removal of showers

• Changes to water storage

• Changes to the people exposed to the risk

• Identification of problems with existing controls

What happens if my business has no Legionella Risk Assessment?

If you are a dutyholder and have failed to properly assess and control a reasonably foreseeable Legionella risk, you may be failing to meet your health and safety responsibilities.

HSE can take enforcement action where dutyholders do not meet their legal responsibilities. Depending on the circumstances, this can include requiring improvements or, where appropriate, prosecution.

More importantly, without an appropriate assessment, you may not know whether your water system contains conditions that could allow Legionella to grow and spread.

The bottom line

If you are responsible for a workplace or commercial premises with a water system, you should not assume that Legionella is irrelevant simply because your building is small or your business is not considered "high risk".

The correct approach is to assess the water system, identify any reasonably foreseeable Legionella risks and put proportionate controls in place where necessary.

A professional Legionella Risk Assessment can help establish what risks exist within your premises and what actions are required to control them.

Need to understand your Legionella risk? Absolute Water Compliance provides Legionella Risk Assessments for businesses across the UK.