The HSE HSG274, “Legionnaire’s Disease: Technical Guidance,” is an important guidance document for handling Legionella bacteria in water systems. The legal requirements covered in this document relate to the Health and Safety at Work etc Act 1974 and the Control of Substances Hazardous to Health Regulations 2002 concerning risks from exposure to Legionella bacteria. It works alongside the ACOP L8, which details how to control Legionella inbuilt systems.
We’ll break down the HSG274 recommendations and explore what they mean for businesses and properties that aim to comply with their legal duties.
What is HSG274?
A Legionella risk assessment is a check of your water system to see if Legionella bacteria could grow anywhere. It looks at how the system is built, where issues might appear, and whether your current safety steps are working. You also get clear advice on what to fix or improve.
It also explains what you need to check regularly so you meet all rules and keep the system safe from Legionella.
The HSE document is divided into three parts:
- HSG274 Part 1: Controlling legionella bacteria in evaporative cooling systems
- HSG274 Part 2: Managing legionella bacteria in hot and cold water systems
- HSG274 Part 3: Handling legionella bacteria in other risk systems
Who is HSG274 For?
This guidance helps you meet your legal duties if you:
- Are a dutyholder
- Are an employer
- Are in charge of premises
- Have health and safety responsibilities for others
What Are the Legal Duties Surrounding Legionella?
These legal duties include:
- Identifying and assessing risks
- Preparing plans to prevent or control risks
- Implementing, managing, and monitoring safety measures
- Keeping records of safety measures
- Appointing a manager responsible for others
What Is Legionnaires’ Disease and How Is It Caused?
Legionnaires’ disease is a lung infection caused by Legionella bacteria. Older adults, smokers, and people with weak immune systems are more at risk. You usually catch it by breathing in tiny water droplets with the bacteria, which is why keeping water systems clean and safe is so important.
You’re more at risk if you:
- Are over 45
- Smoke or drink heavily
- Have chronic respiratory or kidney disease
- Have diabetes, lung, or heart disease
- Have a weak immune system
The good news is that it can be treated with antibiotics.
Control of Legionella Bacteria
Legionella can grow in water if it is warm or sits still. Preventing it is the safest approach. Hot water should be above the temperatures bacteria like, and cold water kept low. Pipes and tanks need cleaning regularly. Checking conditions every so often helps spot problems before they grow. Doing this keeps the water safe and the system reliable.
What Water Systems Are at Risk of Legionella Growth?
Artificial water systems are at risk. Common examples include:
- Spa pools
- Hot tubs
- Swimming pools
- Dental equipment
- Showers
- Healthcare Properties
- Car washes
- Food production sites
- Washrooms
- Factories like manufacturing sites
Legionella in Hot and Cold Water Systems
Water systems, both hot and cold, can allow Legionella to multiply when water warms up or remains unused. Hot water should stay over 60°C, and cold water below 20°C. Taps that aren’t used often should be flushed, and storage tanks cleaned. Testing water and taking occasional temperature readings helps make sure bacteria don’t get a chance to spread, keeping everything safe and in line with HSG274 guidance.
Bacteria in Evaporative Cooling Systems
Cooling towers and other evaporative systems can carry bacteria through tiny water droplets. Managing these systems means keeping water treatment up to date, cleaning components often, and monitoring quality. Drift eliminators need to function correctly to limit droplet release. Regular inspections catch small issues early. These practices reduce the chance of bacteria spreading and maintain compliance with HSG274 standards.
Key Requirements and Recommendations for Legionella Control
Control Measures
Implement key measures for control of Legionella bacteria: keep an eye on temperatures, clean and disinfect regularly, and maintain your systems properly.
Monitoring and Record-Keeping
Keep a record of all monitoring and maintenance activities to stay compliant and track any changes or incidents.
Competence and Legionella Training
Ensure your water system managers are skilled and knowledgeable.
Communication and Collaboration
Good communication and collaboration among staff, contractors, and management are key to making control measures work.
Why You Need a Legionella Risk Assessment for HSG274 Compliance
HSG274 works alongside ACOP L8, which is the Approved Code of Practice from the Health and Safety Executive. It gives guidance on managing Legionella in water systems. The first important step under ACOP L8 is to carry out a Legionella risk assessment following HSG274 guidance.
A word About ACoP L8
ACOP L8 provides guidance alongside HSG274. It outlines what dutyholders need to do, from risk assessments to applying controls and keeping records. Following it isn’t optional; it’s a legal requirement. Doing so protects people and ensures water systems are managed responsibly. You can also use it to demonstrate compliance if inspected or audited.
Approved Code of Practice
The Approved Code of Practice comes from the Health and Safety Executive. It explains how to meet legal duties under the Health and Safety at Work Act. For Legionella, ACOP L8 is the main reference. It covers risk checks, maintenance, and monitoring. Following its advice helps prevent outbreaks and shows that your water systems are cared for safely and properly.
What Does a Legionella Risk Assessment Involve?
A Legionella risk assessment involves both physical and administrative checks to ensure water system safety:
Administrative Checks:
- Check current records and past assessments
- Talk with health and safety team members
- Verify management procedures and paperwork
- Evaluate building occupants’ risk, considering age and health
Tour of the Site:
- Inspect all water systems in the building
- Test for Legionella bacteria in water
- Measure water temperature
- Check areas where aerosols may form
Who Can Carry Out a Legionella Risk Assessment?
The Health and Safety at Work Act of 1974 requires a Legionella risk assessment by a trained, Responsible Person following HSG274 guidelines. Comfort Services Group can help you meet these standards and keep things safe.
How Comfort Services Group Can Help Get You HSG 274 Compliant
Comfort Services Group is a leading UK firm in Legionella control. We provide a range of services to prevent and manage the risk of Legionnaires’ disease. Our services are tailored to the needs of each facility, with a clear reporting system for ACOP L8 and HSG274 compliance. We work closely with our clients, supporting them at every step.
FAQs
How can you remove legionella bacteria in water systems?
The best way to control Legionella in water is to stop it from growing. Keep water very hot or very cold so bacteria cannot survive. Flush pipes and taps often and clean tanks to remove buildup. Sometimes biocides are used. A good system and regular maintenance also help keep water safe.
It is important to check the water often and update risk assessments. Keep records of cleaning, inspections, and treatments. Doing this stops Legionella from growing and spreading. It also keeps the system safe for everyone and shows that safety rules are followed.
How can you better your health and safety at work with HSG274?
Management of health and safety with HSG274 involves several actions. First, assess all water systems for Legionella risks with risk assessments done by qualified staff. Implement control measures like temperature control and system maintenance.
Maintain ongoing staff training to ensure everyone knows their role in keeping water systems safe. Regular monitoring and accurate record-keeping are also important for compliance and adjustments.
What is a high level of Legionella?
High Legionella levels in water systems mean a higher risk of Legionnaires’ disease, requiring quick action. These levels are measured in colony-forming units (CFU) per litre, with anything over 50 CFU/L treated as an actionable item, with remedial course such as re-sampling, cleaning & disinfections to more extreme measures such as shutting down or isolating parts of the system. Once rectified full review of control measures needs to be undertaken. Regular monitoring helps catch any bacteria spikes, keeping things safe and sound.
We are proud to share our experience and knowledge and take pride in offering this to all clients when required. If I, or one of the team can help then please schedule a meeting via the office or get in touch via one of our social media platforms.
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