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Guidelines To Control Legionella

legionella prevention guideline

What Is Legionella?

In water, Legionella bacteria are frequently present. Where there are nutrients available and temperatures between 20 and 45 °C, bacteria thrive. Below 20°C, the bacteria remain dormant, and they cannot thrive over 60°C.

A potentially lethal form of pneumonia known as “legionnaires’ disease” is brought on by breathing in airborne water droplets carrying live Legionella bacteria. Such droplets may be produced, for instance, by atomizers, wet air conditioning units, hot and cold water outlets, whirlpools, or hydrotherapy tubs.

Anyone can get Legionnaires’ disease, but those who are older, smokers, drinkers, have cancer, diabetes, or have chronic renal or respiratory problems are more likely to do so.

The HSE’s Legionnaires’ disease page offers details on minimising risks.

What You Should Do

A thorough risk analysis of their hot and cold water systems should be performed by health and social care providers, who should also make sure that the necessary controls are in place.

Controlling The Temperature

The main strategy for reducing the danger from Legionella is to regulate water temperature.

Water services should be run at temperatures that inhibit the growth of Legionella:

  • Calorifiers, which are containers for hot water, should keep the water at 60°C or above.
  • In areas where there is a scald danger, hot water should be delivered at 50°C or higher; thermostatic mixer valves should be installed as near to exits as practicable.
  • Cold water must be kept below 20°C and supplied accordingly.

According to the risk assessment, a qualified person should regularly examine, inspect, and clean the system.

The outlets that are the farthest and closest to each tank or cylinder must be designated as “sentinel” outlets so that the distribution temperatures may be checked weekly. Additionally, you should check the temperatures of the cold water tank at least once every six months and the hot water storage cylinders at least once a month.

Legionella may develop more readily in stagnant water. To lower the danger, you should flush out seldom used outlets, such as showerheads and taps, at least once a week, and clean and descale shower heads and hoses at least once every three months. Periodically cleaning cold-water storage tanks is advised, and hot water cylinders should have their water emptied to check for corrosion or debris.

Create mechanisms to limit the spreading of Legionella by:

  • minimising the length and directness of pipe runs, properly insulating tanks and pipes, and utilising materials that do not promote Legionella growth
  • preventing contamination, such as by installing bug screens and caps on tanks.
  • Additional safeguards
  • Legionella testing on water samples should be done on a regular basis to show that the levels of bacteria are appropriate. The frequency should be chosen in accordance with the risk assessment and the level of danger.

Other measures of control

Legionella can also be controlled by using biocide treatments (like chlorine dioxide) and ionising copper and silver. They will need to be properly assessed as part of the entire water treatment plan, which includes correct installation, maintenance, and monitoring, in order to stay successful.