Legionnaires Disease

Frequently asked questions about Legionnaires Disease

You can also find tips and advice in our short films on  WaterSafe’s YouTube channel.

What is Legionnaires' disease?

Legionnaires' disease is contracted by breathing in large numbers of the legionella Pneumophila bacteria. These bacteria are widespread in the environment and are able to thrive in warm water conditions. They can be found in water systems, such as hot water tanks, cooling towers and large air conditioning systems. They are more likely to be found in complex plumbing systems.

Water suppliers treat drinking water with chlorine to kill off bacteria. However, they can continue to thrive in plumbing systems which are not installed or maintained correctly, which is why WaterSafe urges homeowners and businesses to only choose qualified and knowledgeable plumbing businesses.

How can I prevent Legionnaires' disease in my home or business?

Top tips to avoid problems with Legionnaires' disease include:

  • Only use a qualified plumber
  • Ensure suitable fittings are used (WRAS-approved)
  • Keep the design of plumbing systems simple
  • Design a system so water is regularly turned over and does not stagnate
  • Ensure hot and cold water are kept at the correct temperatures
  • Businesses should follow the advice within the HSE approved code of practice L8 to ensure they meet their legal duties under the Health and Safety at Work Act 1974 to manage risks from legionella bacteria.

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