All About Legionnaires' Disease


Recently in England and Wales, there were approximately 280 Legionnaires’ disease cases with a mortality rate of 12%. In the more susceptible groups this rate is thought to be in excess of 40%. Most cases were in males over 40 years old. Some 47% of cases are regarded as community acquired, as opposed to hospital acquired (approx 5%), and travel associated (38% abroad, 10% UK), according to data from the National Surveillance Scheme for Legionnaires’ Disease.

In the UK, Legionnaires’ disease has been most commonly associated with hot and cold water systems in large buildings, such as hospitals and hotels, and infections are usually sporadic as opposed to outbreaks with large numbers of people affected. Historically outbreaks have been associated with wet evaporative condensers (cooling towers), but increased controls have reduced incidences.

Well publicised examples of Legionellosis this year include an outbreak on the Black Watch cruise liner which affected 7 elderly people; 80 prisoners were evacuated from a Kent jail as a precautionary measure; and in a Sunderland health club up to 115 people may have been affected with Legionella-like symptoms. Household plumbing systems have also been implicated in sporadic cases of Legionnaires’ disease. In one UK study legionellae were isolated from approximately 15 % of the homes of affected patients in comparison with around 5 % of homes in a control group.

For more informtion on outbreaks and Legionella incidents see the following LINK

What is Legionella?

Legionella is a particularly aggressive form of bacteria that when inhaled in contaminated water droplets rapidly multiplies and produces a severe and potentially fatal form of pneumonia. Legionnaires' Disease mainly affects adults, with men being more at risk than women. The greatest incidence of disease is in men over 40 years of age who also smoke. Persons who are immuno-compromised or suffering from respiratory disorders are also at higher risk.

There are 300-400 identified Legionnaires' Disease cases reported each year in the United Kingdom. There are many more cases that go undetected, estimated figures would suggest 7-8,000.

What is a Risk Assessment?

A suitable and sufficient assessment must be carried out to identify and assess the risk of exposure to legionella bacteria from work activities and water systems on the premises and any precautionary measures needed. The dutyholder is responsible for ensuring the risk assessment is carried out.

Where does a Risk Assessment for Legionella apply?

Where there is a trade, business or other under taking where water is used or stored. The assessment must give details in a way that both technical and non-technical persons can understand.

It must contain:

The Assessment should:

Report on the level of risk of work activities or water systems on the premises that may promote the risk of exposure to legionella bacteria. Where a potential risk is identified, recommend measures to prevent/minimise that risk. If it is not reasonably practicable to eliminate the risk, a plan of detailed action to control the risk is recommended.

Can I get a copy of the  ACOP L8 November 2013?

Yes, here on this page on the attachment to the left or click HERE

Remember that the guidance on how to apply the ACOP L8 is now in a book called (Health & Safety Guidance) HSG 274. Part 1 is for Cooling Towers  etc, Part 2 is for Hot & Cold Water Systems and Part 3 Other Systems.

Why do I need a Risk Assessment?

This Approved Code of Practice 25th November 2013 has been approved by the Health and Safety Executive, with the consent of the Secretary of State. It gives practical advice on how to comply with the law. If you follow the advice you will be doing enough to comply with the law in respect of those specific matters on which the Code gives advice. You may use alternative methods to those set out in the Code in order to comply with the law. However, the Code has a special legal status. If you are prosecuted for breach of health and safety law, and it is proved that you did not follow the relevant provisions of the Code, you will need to show that you have complied with the law in some other way or a Court will find you at fault.

The Approved Code of Practice (ACOP) gives advice on the requirements of the Health and Safety at Work etc Act 1974 (the HSW Act) and the Control of Substances Hazardous to Health Regulations 2002 (COSHH) and applies to the risk from exposure to legionella bacteria (the causative agent of legionellosis, including Legionnaires’ disease). In particular it gives guidance on sections 2, 3, 4 and 6 of the HSW Act and regulations 6, 7, 8, 9 and 12 of COSHH. The Code also gives guidance on compliance with the relevant parts of the Management of Health and Safety at Work Regulations 1999 (the Management Regulations).

The book is for Dutyholders, which includes employers and those with responsibilities for the control of premises.

What is the scope and application

This Approved Code of Practice (ACOP) 2013 applies to the control of legionella bacteria, in any undertaking involving a work activity managed by you or on your behalf. It applies to premises controlled in connection with a trade, business or other undertaking where water is used or stored; and where there is a means of creating and transmitting water droplets (aerosols) which may be inhaled, causing a reasonably foreseeable risk of exposure to legionella bacteria.

Where does legionella naturally occur?

There is a reasonably foreseeable risk of exposure to legionella bacteria in:
(a) cooling systems with cooling towers, evaporative condensers or dry/wet
cooling systems
(b) hot and cold water systems
(c) spa pools
(d) other plant and systems containing water that can create and increase the risk

What type of place is at risk?

Any environment where a number of people come together (particularly the general public)and where water is used or stored i.e. Offices, Hospitals, Nursing Homes, Day Centres, Sheltered Housing Supermarkets, Schools, Factories, Government buildings, Libraries, Leisure complexes, Hotels, etc.

What is the first step in the control of Legionella?

Call Eplus Global Ltd to provide you with a :

Full and proper RISK ASSESSMENT. This is the cornerstone of controlling the bacteria.
Identify and assess the risks
Devise a scheme for controlling the risk
Manage the risk, election and training of competent personnel
Keep records for at least five years.

Can I do it?

Yes. If you do not appoint a responsible person to organise this then the Duty Holder will have to do it. The dutyholder must ensure that the person who carries out the risk assessment and provides advice on prevention and control of exposure must be competent to do so.

If I don't do it, who do I employ to do it for me?

Eplus Global of course.

The dutyholder may need access to competent help and advice whencarrying out the risk assessment. For further guidance on this. This source of advice may not necessarily be from within the person’s organisation but may be from a consultancy, water treatment company or a person experienced in carrying out risk assessments. Eplus Global can help with this. Employers are required to consult employees or their representatives about the arrangements for getting competent help and advice (see paragraph 20).

Employing contractors or consultants does not absolve the dutyholder of responsibility for ensuring that control procedures are carried out to the standard required to prevent the proliferation of legionella bacteria. Dutyholders should make reasonable enquiries to satisfy themselves of the competence of contractors in the area of work before they enter into contracts for the treatment, monitoring, and cleaning of the water system, and other aspects of water treatment and control. An illustration of the levels of service to expect from Service Providers can be found in the Code of Conduct administered by the Legionella Control Association (LCA).

Written by Simon French MWM Soc Dip IHF Exec Dip Man AIOSH AIFL
L8 "Legionnaires' Disease - The control of legionella bacteria in water systems" used as reference