Legionella is a waterborne bacterium that can cause Legionnaires’ disease. Sources of contamination may include domestic hot water installations, shower heads and water networks. The bacteria develop particularly well at temperatures between 25 and 45°C.

How infection occurs

Illness is usually caused by inhaling contaminated water aerosol, for example from a shower. People with reduced immunity are more vulnerable. Early symptoms may resemble flu and include fever, headaches, muscle pain and chills.

How to reduce the risk

Prevention depends on proper design and operation of the domestic hot water installation. It is important to avoid water stagnation, maintain suitable temperatures and regularly inspect the system.

Flow-through domestic hot water preparation can reduce the amount of stored usable water and limit conditions favorable to bacteria. A well-designed buffer tank can therefore support both comfort and hygiene.