What is a Legionella Risk Assessment?
A Legionella Risk Assessment (LRA) is a process used to identify and assess the risks posed by the Legionella bacteria in water systems. LRAs are essential because they can help prevent outbreaks of Legionnaires’ disease. It also minimizes exposure to Legionella-related risks by maintaining cleanliness in potential breeding grounds for the bacteria.
Why Is It Important?
Legionella is a type of bacteria that can cause a severe lung infection known as Legionnaires’ disease. People can become infected with this bacteria by breathing in contaminated droplets of water. It can cause various symptoms, from a mild flu-like illness to severe pneumonia. In some cases, Legionnaires’ disease can be fatal.
Risk assessments are crucial for detecting and mitigating health risks associated with the Legionella bacteria. They help pinpoint areas within water systems where the bacteria may thrive, including air conditioning systems, hot tubs, household plumbing, and areas with warm, stagnant water. With Legionella assessments, property owners can take preventive measures to ensure water quality and comply with legal requirements for safe water systems.
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Is Legionella Risk Assessment a Legal Requirement?
Not all countries require Legionella risk assessment forms or testing. However, it is strongly encouraged by health professionals from different countries, as it can help stop the spread of Legionnaires’ disease. Here’s a quick overview of Legionella compliance requirements around the world:
- United States – Although there is no federal law requiring property managers and landlords to conduct risk assessments or testing of any sort for Legionella, many authorities have argued that it should be done to help promote safer drinking water and protect public health. Some states have specific laws, particularly for cooling towers, water systems, healthcare facilities, and other related buildings.
- United Kingdom – According to the Health and Safety Executive (HSE), landlords and employers are mandated by law to conduct Legionella risk assessments to protect tenants and employees from potential health risks associated with the bacteria.
- Australia – Similar to the US, there’s no specific legal requirement for Legionella risk assessments on a national level in Australia. However, the government has released guidelines for LRAs within facilities.
- Germany – Legionella testing and risk assessments are required for large facilities that regularly heat drinking water, have an internal water storage capacity of more than 400 liters, and have a pipeline volume of at least three liters.
- The Netherlands – Businesses must have their water facilities checked by a certified assessor for the Legionella bacteria at least twice a year. These facilities include hospitals, swimming pools, and other establishments under priority institutions.
How to Conduct a Legionella Risk Assessment
Landlords, employers, and property managers can use the following steps as a guide in performing a Legionella risk assessment and managing Legionella risks:
Step 1: Determine Overall Risk
The first step in carrying out a Legionella risk assessment is to determine if there is a risk. Check if any of the top 3 Legionella-related risk factors are present.
If there is currently no risk, determine if there is a possibility that a risk will occur. If there is no reasonably foreseeable risk, according to the HSE, the Legionella assessment is complete.
If there is a risk, determine the risk level. If the risk level is low and risk is being properly managed to comply with the law, according to the HSE, the Legionella risk assessment is complete. Indications that the Legionella risk level is low (based on examples given by the HSE):
- Use of hot and cold water systems
- Use of small, domestic-type systems
- Regular water usage and turnover
- No stored water tanks
Create your own Legionella risk assessment template
Step 2: Test for Legionella if Needed
To test for Legionella, the HSE recommends doing the following:
- Use the BS 7592 standard for water sampling
- Neutralize biocide if used and where possible
- Submit water sample to a UKAS-accredited laboratory that takes part in a water microbiology proficiency testing scheme
- Ensure that the UKAS-accredited laboratory applies the minimum theoretical mathematical detection limit of <= 100 legionella bacteria per liter of sample for culture-based methods
Aside from cases where control measures do not seem to be effective, Legionella testing is typically only carried out for cooling tower systems. However, it’s also recommended for other open systems, such as evaporative condensers and spa pools. The HSE states these systems should be tested for Legionella at least quarterly.
It’s also good to note that UK law does not require a Legionella test certificate, nor does the HSE recognize it.
Step 3: Fulfill Other Duties
Under the UK Notification of Cooling Towers and Evaporative Condensers Regulations 1992 (NCTEC), the local authority must be notified in writing if there is a cooling tower or evaporative condenser on site, and details about where it is located should be included. The local authority must also be notified when such devices are no longer in use.
Under the UK Reporting of Injuries, Diseases and Dangerous Occurrences Regulations (RIDDOR), cases of Legionellosis (Legionnaires’ disease) in employees who have worked on cooling towers or on hot and cold water systems that are likely to be contaminated with Legionella must be reported.
For properties that are left vacant, water should not be allowed to stagnate within the water system, and outlets on hot and cold water systems should be used at least once a week.
FAQs About Legionella Risk Assessment
While the specifics may vary per region, LRAs must be performed by competent individuals. For instance, the UK’s Approved Code of Practice L8 (ACoP L8) states that the person conducting the assessment and implementing any control measures must have the “necessary expertise, experience, and knowledge.” Moreover, they should be “properly trained to safely and effectively complete their tasks.”
As per industry standards, Legionella risk assessments should be done at least every two years. Per advice by the ACoP L8, assessment must be conducted “more frequently if there is a valid reason to do so” to keep the assessment updated.
In general, LRAs are a must should there be changes that could potentially affect the growth or spread of Legionella bacteria.
A professional Legionella risk assessment can take anywhere from a few hours to a few days, depending on the size and complexity of the property. This can take longer if there are certain restrictions in place on-site.
Some of the most common Legionella-related risk factors include the following:
- Water is being stored or re-circulated as part of the water system
- Sources of nutrients for Legionella, such as rust, sludge, scale, organic matter, and biofilms, are present
- Water droplets are being produced or can be produced
- Water droplets can be dispersed over a wide area (e.g., showers and aerosols from cooling towers)
- Any employee, resident, or visitor is more susceptible to Legionella infection due to age or illness, such as a weakened immune system
- If the person who is more susceptible to Legionella infection could be exposed to any contaminated water droplets
The Health and Safety Executive recommended that landlords take the following simple steps to minimize the risks of Legionella:
- Keep water systems clean and well maintained
- Regularly check and clean showerheads, taps, and other fixtures
- Flush out stagnant water from pipes and tanks
- Keep the temperature of hot water above 60°C
- Fixing faulty or removing redundant pipework
- Keep a record of all maintenance and water quality tests
Rob Paredes
