fbpx

legionella risk assessment and legionella water testing

What is Legionella?

Legionella is a bacteria which can lead to number of serious illnesses, including the most serious Legionnaires’ disease, other known conditions are Pontiac fever and Lochgoilhead fever, but these two are less serious. Legionnaires’ disease can be fatal and is a form of pneumonia, to make matters worse everyone is susceptible to infection. People who are 45 and over, have known lung conditions, impaired immune systems or are heavy smokers or drinkers, are more susceptible to the disease. Legionellosis is the collective term for illnesses associated with legionella bacteria. Legionella bacteria occur naturally in rivers and ponds, but the conditions are rarely right for people to catch the disease from these sources. Instead, people can get infected from inhaling droplets of water from system like air conditioning or hot tubs, where legionella bacteria has been allowed to grow. It is rare to have an outbreak, but it is very serious when there is.

 

How does Legionella enter the body?

Any water system where water is allowed to be stored at temperatures between 20–45 °C has the potential to grow legionella bacteria, this might be in areas where improvements have been made leaving dead-legs (a pipe leading to an outlet through which water flows, but the outlet is unused/rarely used). People cannot be infected by drinking this water, so infection happens when a person inhales droplets of water. This could happen when using showers or from air conditioning when passing under a ceiling unit. 

Legionella risk assessment

As an owner of a business there are responsibilities which include taking precautions to prevent or control the risk of exposure to legionella. These same responsibilities are also shared by building owners or landlords. The first step to taking precautions is to carry out a legionella risk assessment. If unsure of what water system is in place or whether there is risk of infection, then this particular risk assessment should be assigned to a competent person with the necessary skills to conduct the assessment.

The purpose of the assessment is to understand the water system in place, any associated equipment and identify any possible exposure to legionella risk. The assessment should include, management responsibilities, description of the water system, any possible sources of risk, control measures and details of monitoring, inspections, maintenance, and analysis going forward (if identified as required). If the assessor identifies that the risk to the business is insignificant, then you will have satisfied your duty of care and no further action is required. If the assessor identifies risk and details an action plan to work to within the risk assessment, then you must ensure that you designate an internal competent person to address the plan provided. This may require specific health and safety training, during which the designated person will be given the skills to manage the plan and the system going forward. You may also need to send off samples or arrange for samples to be taken as part of your ongoing measures to reduce risk in the workplace. 

 

Legionella water temperature checks template

Because the danger temperature is 20–45 °C, it’s good practice to ensure that your water is operating outside of those limits. If you use a Pilla Management Diary, then you already have a legionella water temperature template included which you will carry out each week. Here’s how to carry out a legionella water temperature check:


Hot water:

  1. Turn on the hot water outlet
  2. Hold the temperature probe thermometer tip facing down under the running water for one minute
  3. Ensure that the temperature reaches at least 50°C within the one minute.
  4. Record the temperature in your Diary.
  5. If the temperature does not reach 50°C within the one minute, it should be recorded and reported to a Manager for corrective action.

Cold water:

  1. Turn on the cold water outlet
  2. Hold the temperature probe thermometer tip facing down under the running water for one minute
  3. Ensure that the temperature reaches below 20°C within the one minute.
  4. Record the temperature in your Diary.
  5. In the case where the temperature is not below 20°C within the 1 minute it should be recorded and reported to a Manager for corrective action.