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Legionella Compliance

The legionella bacteria can cause serious health problems, including Legionnaires’ Disease, which can prove fatal. Fatalities have been kept low because of strict legislation surrounding he mandatory control of legionella.

However, legionella bacteria is classified as preventable as it can be kept under control with the right safety measures and precautions.

Whatever type of business you own, however large or small, you need to be aware of legionella compliance and how it affects your business.

What is Legionnaires’ disease?

Legionnaires’ disease is a type of pneumonia that is caused by Legionella bacteria. This disease is fatal in up to 30% of cases. People who have a weakened immune system, such as smokers, drug users, and the elderly are more susceptible to this disease.

Some of the most common symptoms associated with Legionnaires’ disease are:

  • Pneumonia

  • Muscle aches

  • Fatigue

  • Cough which might bring up mucus or blood

  • Fever

  • Loss of appetite

  • Cold

  • Shortness of breath

  • Confusion or other mental changes

  • And in some cases, death

People catch Legionnaires’ disease by inhaling aerosols containing the legionella bacteria from either water or soil, as the disease is carried in its droplets, often dispersed through aerosol or any outlet with potential to spray.

Although most people respond to antibiotic treatment, some continue to experience health problems after treatment.

The legionella bacterium can also cause Pontiac fever which is a milder illness that has similar symptoms to the flu. This usually clears on its own without the need for treatment.

How often should I get a legionella risk assessment done?

Legionella risk assessments should be reviewed at least once every two years. However, there are certain situations when an assessment is needed more frequently. These include:

  • If any changes have been made to the water system, pipework, or assets

  • If the water system has had a change of use

  • If new regulations are published

  • If your site’s population is more at risk, such as it includes the more vulnerable or those with impaired immune systems.

  • If a legionella outbreak is suspected

  • If positive samples of legionella have been recorded

Furthermore, the larger your business, the more complex your water systems are likely to be, so more frequent assessments are recommended.

Is it illegal for an office not to have a legionella risk assessment?

It is a legal requirement for all UK businesses to conduct a legionella risk assessment to identify any issues that could put employees, customers, and others at risk. This applies to all business owners, regardless of business size and landlords.

The legal requirement for carrying out a legionella risk assessment is defined under the below legislation:

  1. The Health and Safety at Work Act 1974

  2. Management of Health and Safety at Work Regulations 1999

  3. Control of Substances Hazardous to Health Regulations 1999

A failure to carry out a legionella risk assessment can result in stiff penalties. Any prosecution will be carried out by the Health and Safety Executive (HSE).

Why are air-con units susceptible to hold legionella spores?

The legionella bacteria are found naturally in environments that house water. In particular, warm water that is found in hot tubs, cooling towers, hot water tanks, and large plumbing systems.

If your air conditioning units use a water-based system of cooling a refrigerant, then they could become infected with legionella bacteria.

If you have legionella bacteria anywhere else in your building, this could potentially contaminate your air conditioning units which could then spread the bacteria throughout the rest of the building.

That being said, this can be prevented by maintaining a good cleaning and maintenance schedule for all your heating and cooling units, especially any that contain water.

Can employees get legionella from tap water?

While natural water sources do not pose a risk of infection from legionella, this bacterium can make its way into man-made water systems such as air conditioners, hot tubs, taps, and shower faucets, and this can lead to infection, where the bacteria can reproduce to dangerous levels.

Do all companies have a legionella risk assessment?

All companies in the UK should carry out a legionella risk assessment to ensure the safety of their employees and customers. If you do not currently have proof of a risk assessment carried out by an approved assessor, then you need to arrange this as a matter of urgency.

You also need to ensure that your legionella risk assessment is up to date and that if any potential risks are identified, you need to make the necessary changes to ensure that the risk of legionella is minimised.

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