What is Legionnaires' Disease?


Legionellosis is a collective term for diseases caused by legionella bacteria including the most serious legionnaires’ disease, as well as the similar but less serious conditions of Pontiac fever and Lochgoilhead fever.


Legionnaires’ disease is a form of pneumonia which can prove to be fatal and everyone is open to infection. The older you get the higher risk you are of contracting the disease. The risk increases with age, but some people are at higher risk, eg people over 45, smokers and heavy drinkers, people suffering from chronic respiratory or kidney disease, diabetes, lung and heart disease or anyone with an impaired immune system.


To place this into context;

  • there are between 300 - 500 cases reported each year
  • it can take between 2 and 19 days to show by way of symptoms but usually between 6 and 7 days
  • symptoms include, fever, chill, diarrhoea, vomiting, confusion, headaches, severe muscle aches and chills
  • 12% mortality rate of those that contract Legionnaires Disease
  • once contracted the after effects of the disease will last for months or even years and can lead to brain damage and scar tissue being left on the lungs

  • How is Legionnaires Disease contracted?

    Legionnaires’ disease is normally contracted by inhaling small droplets of water (aerosols), suspended in the air, containing the bacteria which is why showers and spa baths are higher risk.


    Certain conditions within the water will increase the risk of legionella such as:

    • Water temperature between 20 and 45 degrees
    • Sources of nutrients such as scale, biofilm, sludge, organic matter and rust
    • Stagnated water that is then recirculated as part of the system

    Recent changes to the Approved Code of Practice (ACOP) include the removal of the 300 litre limit for hot and cold water services. This was an artificially chosen limit and its removal means that all premises with a water system are now within the scope of the revised ACOP. Also, recent research shows that legionella does occur in smaller domestic systems.


    Under Health & Safety Law - Landlords who provide residential accommodation (including short and long stay holiday homes, AirBnB style properties, parks and cottages), and as the person in control the premises or responsible for the water systems in their premises, have a legal duty to ensure that the risk of exposure of tenants to legionella is properly assessed and controlled. This duty extends to residents, guests, tenants and customers.


    Why do you have to comply with the law?

    Legionella bacteria can multiply in hot or cold water systems and storage tanks in residential properties, and then be spread, eg in spray from showers and taps. Although the generally high throughput and relatively low volume of water held in smaller water systems reduces the likelihood of the bacteria reaching dangerous concentrations, you must still carry out a risk assessment to identify and assess potential sources of exposure. You must then introduce a course of action to prevent or control any risk you have identified.


    Health & Safety Law - HSG274 Part 2

    • Legionnaires’ disease: The control of legionella bacteria in water systems. Approved Code of Practice1 gives specific information on the health and safety law that applies. In brief, general duties under the Health and Safety at Work etc Act 1974 (the HSW Act)2 extend to risks from legionella bacteria, which may arise from work activities. The Management of Health and Safety at Work Regulations 1999 provide a broad framework for controlling health and safety at work (see www.hse. gov.uk/risk for more information). More specifically, the Control of Substances Hazardous to Health Regulations 2002 (COSHH)3 provide a framework of duties designed to assess, prevent or control the risks from hazardous substances, including biological agents such as legionella, and take suitable precautions

    Our service

    • We can complete residential Legionella Risk Assessment reports on your behalf
    • We provide Control Management Strategy examples to help you to develop your own individual property strategy
    • We maintain all reports and documents we provide for the required 5 years
    • We provide useful Tenant information guidance leaflets
    • Our staff are City & Guilds accredited risk assessors
    • We are fully insured and conform to Health & Safety Executive (HSE) Legionnaires Diseases Approved Code of Practice (L8 - Fourth Edition) and HSG274 Part 2
    • We offer fixed priced reporting and review assessments for private landlords
    • Discounts are available on multiple properties or for Letting Agents


    Contact us for further information, pricing and to book your appointment

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