How Often to Get a Legionella Risk Assessment by Industry and Why

If you are responsible for a workplace, commercial property, rented accommodation, or public building, understanding and managing the risk of Legionella is an important part of keeping people safe. But once an initial Legionella risk assessment has been completed, another question often follows: how frequently does it need to be done again?

You may find recommendations for annual, two-yearly, or other fixed schedules. In reality, there is no single interval that applies to every site or industry.

Instead, your Legionella risk assessment should remain an accurate reflection of your water systems, how your building is used, and who may be exposed. This means keeping it under review and reassessing the risk when circumstances change.

What Do the Legionella Regulations in the UK Require?

The Legionella regulations that UK organisations need to consider form part of wider health and safety requirements. Duties arise under legislation, including the Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations (COSHH), with further guidance provided by ACOP L8 and HSG274.

These requirements place responsibilities on employers and those in control of premises to identify, assess, and appropriately control foreseeable Legionella risks. However, there is no blanket legal requirement stating that every Legionella risk assessment must be repeated annually, every two years, or at another fixed interval.

Instead, an existing assessment should be reviewed regularly and whenever there is reason to believe it may no longer be valid. This could be because the water system has changed, the way the building is used has altered, existing control measures are no longer effective, or new risks have emerged.

But what does that mean for different industries?

How Often Should Different Industries Review Their Legionella Risk Assessment?

Although the underlying responsibilities are similar, Legionella risks can vary significantly between different premises. The complexity of the water system, frequency of use, and vulnerability of people exposed should all be considered.

Hospitals, Care Homes, and Other Healthcare Environments

Hospitals, care homes, and dental practices require particularly careful water management because some patients, residents, and visitors may be more susceptible to infection. Healthcare premises can also contain extensive water systems with numerous outlets, specialist equipment, and areas that are used at different frequencies.

Alongside ACOP L8 and HSG274, healthcare environments may need to consider relevant guidance within HTM 04-01 and HTM 01-05. Legionella risk assessments should be kept closely under review and reconsidered promptly when systems, facilities, occupants, or operating practices change.

Hotels, Health Clubs, Leisure Centres, and Sports Facilities

Hotels, health clubs, sports centres, and leisure clubs can have numerous showers, changing facilities, and other hot and cold water outlets. Some may also operate swimming pools, spas, and other water-based facilities.

Patterns of water use can fluctuate significantly, too. A hotel may experience seasonal occupancy changes, while a leisure facility could temporarily close areas for maintenance or refurbishment. Changes to facilities, extended periods of low use, refurbishment, or alterations to the water system can all mean that an existing risk assessment needs reviewing.

Schools, Universities, and Public Buildings

Schools, universities, local authority premises, and National Trust or other heritage properties can present their own challenges. Educational buildings may experience extended periods of reduced occupancy during holidays, potentially leaving some outlets unused. Larger campuses and public estates can also contain multiple buildings, complex systems, or older water infrastructure that has been modified over time.

A risk assessment should therefore reflect how the premises currently operate. Changes to buildings, water systems, occupancy, or patterns of use should trigger consideration of whether reassessment is required.

Restaurants, Retail, Hairdressers, and Commercial Properties

Legionella risk management isn’t limited to large or obviously complex sites. Restaurants, shops, hairdressers, offices, and other commercial properties should also consider the risks associated with their water systems. A smaller, relatively straightforward system may be assessed as low risk, but that doesn’t remove the need to initially assess it and ensure appropriate controls remain in place.

For these businesses, reassessment may become necessary following refurbishment, changes to plumbing, alterations in building use, or evidence that existing control measures are no longer sufficient.

Factories and Food Production Facilities

No two factories are necessarily alike, which makes a site-specific approach particularly important. Depending on the premises, a factory or food production facility could contain extensive hot and cold water systems, employee showers, welfare facilities, process water, infrequently used outlets, or cooling systems.

Changes to production processes, machinery, plumbing, building layouts, or employee facilities could alter the original Legionella risk profile. The existing assessment should therefore be reviewed when relevant changes occur and updated where necessary.

Funeral Homes

Funeral homes can contain specialist facilities and water systems that require careful consideration, including areas where appropriate backflow prevention may be particularly important. The correct approach will depend on the individual premises, their facilities, and how the water is used. 

Landlords and Residential Property

Landlords also have responsibilities to assess and control the risk of exposure to Legionella within rented properties. However, another common misconception is that landlords are legally required to arrange a new Legionella risk assessment every year or every two years. There is no prescribed annual or biennial reassessment requirement.

Instead, landlords should periodically review the assessment and reconsider it when circumstances change in their rented buildings, ensuring that the risks identified and measures used to control them remain appropriate.

When Should You Arrange a New Legionella Risk Assessment?

Whatever your industry, the most important question isn’t simply “When was our last assessment?” It is also “Has anything changed since then?”

Reasons to review your existing Legionella risk assessment can include:

• Changes or modifications to the water system
• Building alterations, extensions, or refurbishment
• Changes to how the premises are used
• Significant changes in occupancy or the vulnerability of people using the premises
• Evidence that existing control measures are no longer effective
• Changes to key personnel responsible for Legionella management
• New information about risks or appropriate control measures
• A suspected or confirmed case of Legionnaires’ disease associated with the water system

Keeping your assessment under review helps ensure that Legionella controls continue to reflect the building as it exists and operates today, rather than how it operated several years ago.

Not Sure Whether Your Legionella Risk Assessment Is Still Valid?

If you’re unsure whether your current assessment remains suitable, we can help you understand your responsibilities and determine the appropriate next steps. As the Legionella People, we provide Legionella Risk Assessments for organisations across the UK, working with clients throughout healthcare, education, leisure, hospitality, manufacturing, retail, the public sector, and other commercial environments.

Our approach is tailored to your premises and requirements. We can help you work towards compliance with ACOP L8 and HSG274, as well as HTM 04-01 where applicable, while providing clear reporting and practical guidance on any actions required. Where further support is needed, we can also provide ongoing Legionella control services and remedial works.

Speak to us today to discuss your premises, arrange a Legionella Risk Assessment, or request a quotation.ay and speak to one of our Legionella specialists.y to answer your questions, provide a competitive quotation, and help you find the right solution for your property or portfolio.