Legionella Risk Assessments
Controlling Legionella risks is crucial for ensuring the work environment is safe for employees. Legionella bacteria can be found in man-made water systems such as hot and cold water systems, cooling towers and evaporative condensers. Water contaminated with Legionella bacteria can cause Legionnaires’ disease – a serious and potentially fatal form of pneumonia.
What you MUST do
Duties under the Health and Safety at Work etc Act 1974 (HSWA) extend to risks from legionella bacteria, which may arise from work activities. The Management of Health and Safety at Work Regulations (MHSWR) provide a broad framework for controlling health and safety at work. More specifically, the Control of Substances Hazardous to Health Regulations 2002 (COSHH) provide a framework of actions designed to assess, prevent or control the risk from bacteria like Legionella and take suitable precautions. The Approved Code of Practice: Legionnaires’ disease: The control of Legionella bacteria in water systems (L8) contains practical guidance on how to manage and control the risks in your system.
As an employer, or a person in control of the premises, you are responsible for health and safety and need to take the right precautions to reduce the risks of exposure to legionella. You must understand how to:
- identify and assess sources of risk
- manage any risks
- prevent or control any risks
- keep and maintain the correct records
- carry out any other duties you may have
Carrying out a risk assessment is your responsibility. You may be competent to carry out the assessment yourself but, if not, you should call on help and advice from either within your own organisation or from outside sources, eg consultancies.
You or the person responsible for managing risks, need to understand your water systems, the equipment associated with the system such as pumps, heat exchangers, showers etc, and its constituent parts. Identify whether they are likely to create a risk from exposure to legionella, and whether:
- the water temperature in all or some parts of the system is between 20–45 °C
- water is stored or re-circulated as part of your system
- there are sources of nutrients such as rust, sludge, scale, organic matter and biofilms
- the conditions are likely to encourage bacteria to multiply
- it is possible for water droplets to be produced and, if so, whether they can be dispersed over a wide area, eg showers and aerosols from cooling towers
- it is likely that any of your employees, residents, visitors etc are more susceptible to infection due to age, illness, a weakened immune system etc and whether they could be exposed to any contaminated water droplets
Your risk assessment should include:
- management responsibilities, including the name of the competent person and a description of your system
- competence and training of key personnel
- any identified potential risk sources
- any means of preventing the risk or controls in place to control risks
- monitoring, inspection and maintenance procedures
- records of the monitoring results and inspection and checks carried out
- arrangements to review the risk assessment regularly, particularly when there is reason to suspect it is no longer valid
If you conclude that there is no reasonably foreseeable risk or the risks are low and are being properly managed to comply with the law, your assessment is complete. You may not need to take any further action at this stage, but any existing controls must be maintained and the assessment reviewed regularly in case anything changes in your system.
Types of Risk Systems
If you have a cooling tower or evaporative condenser, you should put in place appropriate measures to prevent or control the risk of legionella as described in Legionnaires’ disease: The control of Legionella bacteria in water systems.
Otherwise, other measures need to be put in place to prevent or control the risk from legionella and must be as equally effective.
- Types of evaporative cooling equipment (paras 1.13-1.21)
- Management of evaporative cooling systems (paras 1.22 – 1.31)
- Design and construction
- Management of cooling systems
- Requirements of a cooling water treatment programme (paras 1.32 – 1.74)
- Microbial control
- Corrosion control
- Scale control
- Fouling control and physical cleanliness
- Conventional chemical water treatment
- Alternative treatment techniques
- Inspection, cleaning and disinfection (paras 1.75 – 1.113)
- Cleaning and disinfecting a cooling system
- Inspecting a cooling system
- Interpreting the findings of the inspection
- How clean does the cooling tower pack need to be
- Cleaning and disinfection procedure
- Monitoring water quality (paras 1.114 – 1.129)
- General monitoring and analysis
- Monitoring for Legionella
Frequently asked questions
The ACOP L8 regulations indicate that a suitable and sufficient risk assessment is the first step in Legionnaires’ Disease prevention. The objective is to identify all water systems where legionella bacteria could potentially grow and assess the risk of people being exposed to contaminated aerosols from them. All water systems need to be included in the legionella risk assessment, but particular attention needs to be paid to
- Hot & cold water systems
- Cooling water systems/cooling towers and evaporative condensers
- Spa pools
- Spray humidifiers, misters, air washers and wet scrubbers
- Safety showers, sprinklers, vehicle wash systems
- Fountains and water features
- Any other system containing water in which Legionella could grow and be released in aerosol droplets
The ACOP L8 regulations say that if you are an employer, or control premises or water systems in connection with work, then you need to carry out a legionnaires risk assessment of each of your water systems. The assessment must be carried out by trained personnel who are competent to do so. Despite what some people might tell you, you can do it yourself, provided you know what you are doing and, if you are responsible for a number of simple water systems, this may be a cost-effective approach. We can provide bespoke training and document systems to enable you to do your own risk assessment for legionella and develop you own legionella disease control measures.
Obviously, if your water systems are more complex, we would recommend that you get expert help and Sci-Tech water Treatment can carry out a comprehensive risk assessment for legionella on your behalf.
The ACOP L8 regulations say that the Legionnaires’ risk assessment should be reviewed regularly and specifically whenever there is reason to suspect it is no longer valid. The guidance used to say that a legionella risk assessment should be reviewed at least every 2 years but now it says the risk assessment should be a living document which must be regularly reviewed to ensure it remains up to date. In practice this still means that, although L8 no longer puts a time-frame to it, the risk assessment should be reviewed at least every 2 years and any time there is a significant change such as if you have added to or modified your water systems, the use of the water system has changed, key personnel have changed or your legionella control measures are no longer working.
For a simple system the risk assessment review may be fairly straight forward, but for more complex systems it is best to carry out a full legionnaires risk assessment from scratch.
Legionella L8 risk assessments are only the first step in legionnaires disease prevention. In addition, the statutory duty holder also has to:
- Prepare a scheme for preventing or controlling the risk
- Implement and manage precautions
- Keep records of precautions implemented
- Appoint a person to be responsible
Often overlooked, it is actually a requirement for landlords to have a legionella risk assessment on their property to ensure risks are highlighted and remedial actions taken to ensure tenants are protected. While this is a requirement, landlords of single dwellings can perform this assessment themselves so long as they have the right awareness training. One thing landlords do not need to do is perform Legionella water analysis, merely ensure risk is managed.
If you own single dwellings which are let to the public then performing a risk assessment isn’t a difficult task, to teach landlords to perform these assessments themselves we have put together a package which includes a video course and supporting materials, we also include a Pro-Forma to fill out to perform the assessment. For landlords in charge of larger complexes such as blocks of apartments then an assessment by a trained assessor will be required.
If you have any questions about Legionella Risk Assessments. Contact Us