Guide on Legionella Health Safety UK

Businesses are concerned over the recent outbreak of legionella. According to legionella health safety UK guidelines, the public must get medical treatment as soon as they experience symptoms of the illness.



The legionella bacteria are responsible for the pneumonia-like illness collectively known as Legionellosis. Legionnaire’s disease is a fatal illness that can infect everyone. People have a higher risk of contracting the disease if they are 45 years of age or above, heavy drinkers, smokers, suffering from chronic kidney or respiratory disease, or have a weakened immune system.


The bacteria are found in natural water systems including lakes, rivers and reservoirs. They are also common in man-made water structures such as evaporative condensers, whirlpool spas, and cooling towers. The bacteria can proliferate if the conditions are favourable. According to the legionella health safety UK guide, most of the outbreaks are linked to legionella growing in man-made water systems.


People get legionnaire’s disease by inhaling air or water that has the bacteria. Its symptoms are same as the flu that includes fever, high temperature, chills, muscle pains, cough, and headache. In severe cases, people suffer from pneumonia and show some signs of mental confusion.


According to legionella health safety UK authorities, there are risks of the disease in the workplace as long as it has a water system that can be a source of bacteria growth. There are risks of legionella if the water system has water temperature from 20 to 45 °C, spreads droplets, stores water, and has a source of food for the bacteria.


Cooling tower and hot and cold water systems are also considered as common sources of the bacteria. Legionella health safety UK guidelines also list air washers, humidifiers, indoor decorative fountains and emergency showers as other sources of the bacteria.


Employers and building owners must do their best to control the risks of the bacteria growth. Legionella health safety UK authorities state that business owners are responsible for taking the necessary precautions to decrease the risks of exposure to the bacteria. They must identify the sources of risk, manage the risks, prevent risks from happening in the future, keep records, and carry out other duties regarding the safety of people in the workplace.


Employers must have a written risk assessment for the water systems in the workplace. It must have a description of the system that includes the most recent blueprint of the system. The workplace is safe from legionella outbreaks if the risk assessment concluded that there is no significant growth of the bacteria.


Testing for open water systems must be done every quarter but there are instances when sampling must be done more frequent. For closed water systems, testing is done only when it is necessary according to the risk assessment for legionella. Authorities will conduct the tests on the water samples to find out if there are signs of legionella growth.


Employers and building owners can appoint someone to monitor the presence of the bacteria as stated by the legionella health safety UK standards. Authorities said that anyone can be one as long as they have the skills to implement strategies and control measures.

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