The Health and Safety Executive publish Approved Codes of Practice (ACOPs) where approval has been gained by the HSE Board with the consent of the Secretary of State. The ACOP L8 applies to the control of Legionella bacteria and describes preferred or recommended methods that can be used to comply with the regulations and the duties imposed by the Health and Safety at Work Act 1974. By following the advice dutyholders comply with legal requirements in this regard.

Identification and assessment of the risk

Dutyholders include employers and those with responsibilities for the control of premises who should identify and assess sources of risk. Identifying the risk includes checking whether conditions will encourage bacteria to multiply such as water temperature of between 20–45 °C and the presence of a means of creating and disseminating breathable droplets. It also includes identifying the presence of people susceptible to the contaminated aerosols.

As part of the risk assessment, it is necessary to take into account the individual nature of each site and consider the system as a whole rather than the parts in isolation. In complex systems, a site survey of all the water systems should be carried out, including an asset register of all associated plant, pumps, strainers and other relevant items. This should include an up-to-date schematic diagram showing the layout of the plant or system, including parts temporarily out of use. Brodex can provide a documented Legionella risk assessment overview including pipework schematics and photographic evidence.

Managing the risk including management responsibilities, training and competence

According to ACOP L8 if the assessment shows that there is a reasonably foreseeable risk and it is reasonably practicable to prevent exposure or control the risk from exposure, the dutyholder is also responsible to 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.

Preventing or controlling the risk from exposure to Legionella bacteria

Where the assessment shows that there is a reasonably foreseeable risk of exposure to legionella bacteria, the use of water systems, parts of water systems or systems of work that lead to exposure must be avoided so far as is reasonably practicable. Where this is not reasonably practicable, there should be a written scheme for controlling the risk from exposure that should be properly implemented and managed. The written scheme should specify measures to take to ensure that it remains effective.

Record keeping

The regulations require employers, who have five or more employees, to record the significant findings of their risk assessment and the steps taken to prevent exposure to substances hazardous to health.

Those appointed must ensure appropriate records are kept. These records should be retained throughout the period they are current and for at least two years afterwards. Additionally, they must retain records of any monitoring inspection, test or check carried out, and the dates, for at least five years.

Responsibilities of designers, manufacturers, importers, suppliers and installers

The L8 Code and guidance also sets out the responsibilities of suppliers of services such as water treatment and maintenance and of designers, manufacturers, importers, suppliers and installers of water systems to ensure that they are safe and without risks to health at work and that any information related to the article or substance is provided.

Full details are available at http://www.hse.gov.uk/pubns/books/l8.htm