Protecting your water system from the Legionella bacteria requires a thorough risk assessment. Find out how to perform a Legionella risk assessment with this guide.
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.
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.
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:
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.
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.
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.
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.
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.
Landlords, employers, and property managers can use the following steps as a guide in performing a Legionella risk assessment and managing Legionella risks:
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
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.
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.
Mitti (by SafetyCulture) is a mobile-first operations platform adopted across industries such as manufacturing, mining, construction, retail, and hospitality. It’s designed to equip leaders and working teams with the knowledge and tools to do their best work—to the safest and highest standard.
Efficiently manage and streamline health and safety processes across the organization, including incident management, safety audits and inspections, risk assessment, waste management, and more, using a comprehensive construction safety solution.
✓ Save time and reduce costs
✓ Stay on top of risks and incidents
✓ Boost productivity and efficiency
✓ Enhance communication and collaboration
✓ Discover improvement opportunities
✓ Make data-driven business decisions
