Water Hygiene Risk Assessment in accordance with:
ACop L8 4th Edition 2013
Legislation and risk factors
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 potentially fatal form of pneumonia and everyone is susceptible to infection. The risk increases with age, but some people are at higher risk, e.g. 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. The bacterium Legionella pneumophila and related bacteria are common in natural water sources such as rivers, lakes and reservoirs, but usually in low numbers. They may also be found in purpose-built water systems, such as cooling towers, evaporative condensers, hot and cold water systems and spa pools. If conditions are favourable, the bacteria may multiply, increasing the risks of Legionnaires ’ disease, and it is therefore important to control the risks by introducing appropriate measures. Legionella bacteria are widespread in natural water systems, e.g. rivers and ponds. However, the conditions are rarely conducive for people to catch the disease from these sources. Outbreaks of the illness occur from exposure to legionella growing in purpose-built systems where water is maintained at a temperature high enough to encourage growth, e.g. cooling towers, evaporative condensers, hot and cold water systems and spa pools used in all sorts of premises (work and domestic) Legionnaires’ disease is normally contracted by inhaling small droplets of water (aerosols), suspended in the air, containing the bacteria.
Certain conditions increase the risk from legionella if:
(a) The water temperature in all or some parts of the system may be between 20–45 °C, which is suitable for growth; (b) It is possible for water droplets to be produced and if so, they can be dispersed; (c) Water is stored and/or re-circulated; (d) There are deposits that can support bacterial growth, such as rust, sludge, scale, organic matter and biofilms; (e) If susceptible people breath the contaminated aerosol It is important to control the risks by introducing measures which do not allow proliferation of the organisms in the water systems and reduce, so far as is reasonably practicable, exposure to water droplets and aerosol. This will reduce the possibility of creating conditions in which the risk from exposure to legionella bacteria is increased.
The current legislation and guidance is:- The Health and Safety at Work Act – 1974 - COSHH The Approved Code of Practice and Guidance L8, "Legionnaires’ Disease - The Control of Legionella Bacteria in Water Systems" (ACoP L8 4th edition 2013)
All systems require a risk assessment, however not all systems will require elaborate control measures. A simple risk assessment may show that the risks are low and being properly managed to comply with the law. In such cases, you may not need to take further action, but it is important to review your assessment regularly in case of any changes in your system, and specifically if there is reason to suspect it is no longer valid i.e. a) Changes to the water system or its use. b) Changes to the use of the building in which the water system is installed. c) The availability of new information about risks or control measures. d) The results of checks indicating that control measures are no longer effective. e) Changes to key personnel or tenants that may be susceptible or high risk f) A case of Legionnaires’ Disease / Legionellosis is associated with the system. g) changes in either the management, service provider of the system or where new construction work is expected to be carried out. Risk - To assess the risk of exposure to Legionella Bacteria related to water on these premises. Hazard - Inhalation of water droplets containing Legionella bacteria. Who is at risk? - Residents, guests, tenants, customers, staff, contractors, vulnerable people in higher risk categories.
This is the person who is in control of the premises or systems in connection with work and risk from systems in buildings e.g. a building is let to tenants, but the landlord is responsible for maintenance and ensuring the risk assessment is carried out. The risk assessment also enables the duty holder to show they have considered all the relevant factors, and the steps needed to prevent or control the risk
The duty holder should specifically appoint a competent person to take day-to-day responsibility for controlling any identified risk from legionella bacteria, known as the 'responsible person'. It is important for the appointed responsible person to have sufficient authority, competence and knowledge of the installation to ensure that all operational procedures are carried out effectively and in a timely way. Those specifically appointed to implement the control measures and strategies should be suitably informed, instructed and trained and their suitability assessed. They must be properly trained to a level that ensures tasks are carried out in a safe, technically competent manner; and receive regular refresher training. Keep records of all initial and refresher training. If a duty holder is self employed or a member of a partnership, and is competent, they may appoint themselves.
Site Management Responsibilities
Action if not present -A suitable secure fitting lid is required to prevent debris and contamination build up
Responsibility - Landlord/appointed representative
Action slight debris - Maintain and check annually following regular use of the system
Action moderate debris - Drain the system and clean the tank thoroughly removing all debris and contamination
Action highly contaminated - Drain the system and clean the tank thoroughly removing all debris and contamination with adequate disinfection process
Responsibility - Landlord/competent person or appointed representative
Action if not present - Suitable and well fitted insulation is required to maintain cold water stored temperatures.
Action - Ensure regular turnover of water through all outlets at least once a week
Responsibility - Tenant or landlord / appointed representative if property is unoccupied
Action if not present - Adequate insulation should be fitted at the earliest opportunity to enable the water to be stored at the set temperature for longer periods, this will aid economic efficiency of the system
Action - Temperatures are controlled at the cylinder and should be set at 60 degrees centigrade. Combination boilers are controlled at the boiler or by reducing/increasing the rate of flow at the hot tap. . Take care when running hot water as it may scald if set too high and should be bearable to keep your hand under without pain.
Responsibility - Inform the landlord/appointed representative if hot water is not able to be controlled.
Action if present - Flush regularly at least weekly to prevent stagnation in pipework
Responsibility - Landlord/ Tenant/ Appointed representative
Action if present - Good practice is to remove all deadlegs if reasonably practicable as water stagnates in pipework and could drag back into the system.
Responsibility - Competent person, contractor or consultant
Action - If unoccupied for longer than 4-6 weeks, the system should be cleaned, disinfected and thoroughly flushed prior to re-letting.
Responsibility - Tenant or landlord / appointed representative.
Action - Due to the high risk they impose, we advise that these are not used by the tenants during the tenancy. The water needs to be drained from the tub, thoroughly cleaned internally and a secure lid fitted advising tenants that the item is not to be used.
Responsibility - The landlord or professional competent person.
Shower heads, spray taps, whirlpool jets and all outlets.
Action - Keep clean and free of lime scale to prevent contamination. Descale quarterly or replace if required.
All internal /external taps, shower heads, whirlpool jets, storage tanks, bidets and little used outlets.
Action - Ensure a regular / weekly flushing regime to eliminate stagnation in pipework by turning on taps, flushing toilets and showerheads for a few minutes
Action - If present ensure they are adequately maintained as per manufacturer's instructions
Each recommendation made in the assessment is assigned a priority rating, dependent upon the level of risk and / or the seriousness of the contravention of health and safety legislation / guidance it represents. Where an imminent risk to health and safety is found during an assessment, this will have been communicated to the Responsible Person as soon as practicable.
Where harm may occur and changes to practices/ equipment etc. are recommended within a suitable time frame to reduce/ minimise risk
Where harm is seldom to occur, although any change in low risk findings/ practices may alter the risk rating.
Where harm is unlikely to occur. This represents good practice and indicated minimal risk if practices are continued
All of the recommendations / actions should be implemented only by persons / contractors and consultants competent to do so