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What Is a Legionella Risk Assessment (LRA)?

A Legionella risk assessment is a process used to help identify and assess the potential risk factors within buildings, premises and facilities. The findings are then used to pinpoint what interventions are required and the protocols and systems that need to be put in place in order to establish robust Legionella risk controls. LRAs are essential because they can help to prevent outbreaks of Legionnaires’ disease.

Is a Legionella Risk Assessment a Legal Requirement?

Under UK Health and Safety law – landlords, business owners, employers and property managers are legally required to assess, mitigate and consider the risk of Legionella within their business or property. Care home and other facilities where residents are likely to be at high risk of infection need particular consideration.  You can reference the HSG274 Part 2 regarding this.

What does a Legionella Risk Assessment Entail?

A Legionella risk assessment is the first step to help ensure a Legionella compliant property for its occupants and for those responsible to prove they have taken the necessary steps needed to keep people safe.

LRAs involve two processes: physical inspection and risk assessment.

The physical inspection involves the following process:

  • Assessment and documentation of the site, including water tanks and pipework designs with photographic proof

  • Water supply and temperature testing at critical locations throughout the facility

  • Conducting water flow and stagnation tests

  • Inspection for hazards caused by aerosols

  • If deemed necessary, testing water samples from different parts of the water system

Risk assessment involves the following process:

  • Review of previous assessments and any available water testing data

  • Identification of potential sources of Legionella contamination

  • Evaluation of the risks posed by these sources

  • Determination of the need for additional control measures

A report is then prepared that documents the assessment findings and outlines any recommended control measures.

If I am not storing hot or cold water in my system, do I need to carry out a risk assessment?

Yes. There may be other factors within your system that increase the risks of legionellosis, eg deadlegs, showerheads and/or long runs of pipe work containing warm water. A risk assessment should also consider anyone who could be potentially exposed to any legionella bacteria in your system, and particularly groups that are at a higher risk of contracting legionellosis. However, once you have completed your risk assessment you may decide that the risks are insignificant.

How long does a professional Legionella Risk Assessment take?

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.  Longer if there are certain restrictions in place on-site.

How can I minimise the risks of Legionella?

The Health and Safety Executive recommend that landlords take the following simple steps to minimise 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 degrees Celsius

  • Fix faulty or remove redundant pipework.

How often is a Legionella Risk Assessment required?

There are guidelines on how often legionella risk assessment ought to be carried out.  However, the recommended assessment intervals will vary according to the nature of the system being assessed.  Another factor determining this would be the nature of the results acquired after testing.  Positive results will require further testing to ensure the effectiveness of measures implemented to destroy microbial life.

How quickly will I get results from a sample collection?

Once samples have been collected, they are delivered to the laboratory for analysis within 24 hours.  Results usually take approximately 14 days to come back.  The results will then determine what actions need to be taken. 

Why do my tanks need cleaning?

Once water is stored it is then open to the environment and therefore susceptible to contamination and degradation. This can allow conditions to develop which supports the growth of micro-organisms. To maintain water quality, the Health & Safety Executive (HSE) recommends regular inspection of water storage tanks, calorifiers and cooling systems and to clean and disinfect them if necessary.

The proliferation of Legionella can occur due to sludge and nutrient build-up in water services. For this reason, ACoP L8 recommends the cleaning and disinfection of cooling systems twice yearly. For other domestic systems such as water storage tanks, cleaning and disinfection are only necessary if routine inspection shows it to be required.

Why choose Envirisk for your Legionella Compliance
and Water Management Services?

Every member of the Envirisk team is trained to the highest industry standards to ensure that the service that we deliver is fully compliant with all current legislation and guidance including the Health & Safety at work Act (1974) and HSE Approved Code of Practice (ACOP) L8 HSG274. Accredited training is provided by PPL Training. Envirisk’s own training modules include Health & Safety, COSHH, correct use of RAMS and environmental training.

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