Walking into a restaurant, hotel, or office building in the UK, have you ever wondered, “Is the water here safe?” If harmful bacteria contaminate the water systems, it could pose a severe health risk to anyone exposed. Unfortunately, this concern is valid. Contamination by Legionella bacteria occurs more often than you may realise. Proper management and preventative measures are critical to avoid outbreaks.
In this blog post, we’ll explore what facility managers need to know about Legionella risks. I’ll outline the key elements to include in an effective Legionella management plan based on UK regulations and guidance. My goal is to provide practical guidance on protecting your building occupants from harm. A sound legionella management plan, consistently implemented, can prevent Legionnaires’ disease and save lives.
What is Legionella and Why Should You Care?
First, a quick reminder on Legionella if you’re not familiar with it. Legionella is a type of bacteria commonly found in natural freshwater environments like ponds and streams. It becomes hazardous when it colonises and spreads within human-made water systems. Cooling towers, hot tubs, plumbing systems, and hot water tanks can provide ideal conditions for Legionella to thrive.
The biggest health risk is when people inhale small droplets of water contaminated with the bacteria. This could happen through air conditioning systems, showers, fountains, or other aerosolised water sources. Legionella infection causes Legionnaires’ disease, a severe form of pneumonia that can be fatal in up to 25% of cases. According to Public Health England, there are around 500 reported cases of Legionnaires’ disease each year in the UK. Outbreaks across the UK and Europe demonstrate the critical need for proper control.
Anyone exposed to contaminated aerosols can get sick, but the elderly, smokers and those with weakened immune systems are particularly susceptible. As a facility or building manager in the UK, you have a responsibility to protect your occupants’ wellbeing. Safeguarding your water systems from Legionella colonization is a necessary part of risk management and a legal requirement under the Health and Safety at Work etc Act 1974.
The Purpose and Scope of a Legionella Management Plan
A Legionella management plan serves as your proactive strategy to minimise risks within your water systems. It documents all policies, procedures, and responsibilities pertaining to Legionella control in your building(s) as specified in the Approved Code of Practice L8. The primary goal is to prevent Legionella from growing and spreading within the plumbing infrastructure.
The legionella management plan should cover all water sources under your management where Legionella could grow, including:
- Cooling towers
- Hot and cold potable water systems
- Hot tubs
- Decorative fountains or water features
- Large plumbing systems
- Fire sprinkler systems
It’s wise to scope your legionella management plan as broadly as possible. Even areas that may seem insignificant can pose a hazard. For example, an infrequently used bathroom on the fourth floor could have stagnant water where Legionella proliferates, putting anyone who uses it at risk.
Background Info: Legionella Bacteria and Transmission
To understand how to control Legionella, you need a basic understanding of what it is and how people get infected.
Legionella bacteria are ubiquitous in natural aquatic environments, but concentrations are low enough that illnesses are rare under normal conditions. Problems arise when the bacteria grow and spread widely in man-made water sources.
Certain physical and chemical water conditions encourage Legionella growth:
- Temperatures between 20-45°C. Ideal growth occurs at 37°C.
- Stagnant or slow-moving water
- Sediments, sludge, rust, and scale that can shield bacteria
- Certain free-living amoeba that can harbor Legionella
Once Legionella colonies are established, transmission happens via inhalation of contaminated aerosols. Aspiration of contaminated water into the lungs can also infect in severe cases.
It’s impossible to keep Legionella out of building water systems entirely. Low concentrations may come in through municipal water supplies. The goal is to prevent extensive colonisation and limit occupants’ exposure below unsafe levels per HSG274 guidance.
Legionella Management Plan Responsibilities and Training
Proper Legionella management requires coordination between maintenance, facilities, and upper management teams. Define each party’s duties clearly in your legionella management plan as stated in the HSE’s Approved Code of Practice L8.
As a minimum, designate one knowledgeable person to serve as your “Responsible Person” or “Duty Holder” for oversight of the Legionella program. This person should have the authority to make any needed repairs, modifications or disinfections.
The Responsible Person’s duties may include:
- Overseeing all Legionella risk assessments
- Ensuring water monitoring and treatments stay up to date
- Maintaining full training for facilities staff
- Keeping detailed logs of all control activities
- Responding promptly if contamination is suspected
Facility maintenance teams will carry out crucial day-to-day Legionella prevention tasks. Provide specialised training on your water systems, routine inspections, sampling procedures, treatments, and documentation as advised by HSE guidance. Schedule refresher training annually.
Start With a Thorough Legionella Risk Assessment
Preventing Legionella growth involves proactive risk management. Your legionella management plan should include procedures for periodic water system assessments as stated in regulation HSG274. Identify all areas potentially conducive to Legionella growth so you can implement targeted controls.
A comprehensive legionella risk assessment includes:
Physical Water System Evaluation
A detailed inspection of all water sources to identify:
- Dead legs or stagnant sections of pipe
- Sediment buildup that can provide food for bacteria
- Sections where water may not reach adequate temperatures, including distal taps
- Locations where aerosols may be generated, like cooling towers and shower heads
- Tank condition and placement
- Water hammer issues
Water Sampling and Testing
Collect samples from both hot and cold water systems, especially in areas identified as higher risk. Testing should include:
- Culture analysis for Legionella bacteria
- Verification of effective water temperatures
- Testing for scale, sediments, microbial growth, and corrosion
Analysis of System Vulnerabilities
Review water system layouts, equipment specifications, and maintenance procedures to pinpoint risks. Assess vulnerabilities like:
- Water heater placement and capacity
- Piping configurations that can create low-flow or dead-end sections
- Inadequate tank insulation allowing temperature loss
- Infrequent flushing of low-use outlets
Re-assess both the physical infrastructure and water quality at least yearly, or whenever significant changes are made to the water systems.
Apply Preventive Measures Tailored to Your Water Systems
Once you’ve completed a risk analysis, use the results to inform targeted control strategies aligned with UK guidelines. Your Legionella management plan should document all procedures implemented to discourage bacterial growth.
Here are key strategies to include:
Ensure Hot Water Stays Hot
Temperature control is critical! Legionella dies rapidly at temperatures above 60°C. Storage tanks should be set to at least 60°C and hot water circulating loops maintained at 50°C or higher as advised by HSG274.
At taps, hot water should reach 50°C within one minute. If not, take corrective actions like insulating pipes or repositioning circulators.
Keep Cold Water Clean and Cool
Though not optimal for extensive Legionella growth, cold water below 20°C can allow survival. Disinfect tanks periodically and avoid water stagnation. Properly maintain chillers.
Implement Biocide Treatments
Introducing disinfectants helps limit Legionella. Chlorine, chlorine dioxide, copper-silver ionization, monochloramine, ozone, and UV treatment are options.
Ensure proper dosing and monitoring to maintain effective residual disinfectant levels per BSRIA guidance.
Clean and Disinfect Cooling Towers Regularly
Due to warm water, scale, and sediments, cooling towers pose some of the highest risks. Follow stringent maintenance procedures like:
- Continuous biocide treatment
- Quarterly disinfections
- Routine visual inspections
- Sediment removal
- End-of-season draining and cleaning
Remove or Flush Stagnant Water Sections
Any water that sits stagnant allows potential Legionella growth. Routinely flush low-use taps, dead-end pipes, and tank drains. Alternatively, remove unused sections altogether.
Keep Detailed Records
Maintain logs for all water system maintenance, biocide dosing, disinfections, temperature monitoring, and other control activities. Thorough record-keeping is crucial!
By tailoring prevention measures to risks in your water systems, you can target problem areas effectively. Consistent, proactive control is key.
Implement Ongoing Monitoring to Ensure Safety
Once Legionella preventive measures are in place, back them up with vigilant monitoring procedures. Your Legionella Management Plan should outline oversight activities and how often they are performed based on HSE guidance.
Typical monitoring includes:
Measure temperatures weekly at representative hot water outlets and tanks. Also, sample cold water to ensure proper chillers operation.
Biocide Level Testing
If disinfectants are used, test residuals monthly or more frequently to ensure efficacy.
Water Quality Analysis
Periodically take samples to test for Legionella via culture, along with sediments, microbial growth, and corrosion.
Equipment Function Checks
Verify thermostats, circulating pumps, automatic valves, and dosing systems are working properly.
Visual System Inspections
Look for issues like biofilm buildup, leaks, or damage that could spur Legionella growth.
Review maintenance logs and records regularly for completion.
Catching any control lapses or deviations promptly is crucial for ongoing safety. Specify procedures for corrective actions if thresholds aren’t met.
Keep Detailed Records for Oversight and Verification
Thorough recordkeeping and documentation is at the core of effective Legionella management. Your legionella management plan should detail the maintenance of accurate logs by designated staff. Tracking activities provides oversight and ability to verify system control, as mandated by ACoP L8.
Documents to maintain include:
- Risk assessment reports
- Water system descriptions, layouts, and schematics
- Temperature monitoring logs
- Water quality testing results
- Biocide dosing and residual measurements
- Cleaning and disinfection procedures completed
- Plumbing repairs or modifications
- Staff training records
Both paper and digital copies should be kept for at least 5 years as specified by regulation. Records serve as proof of your diligent control efforts. They also aid troubleshooting if issues arise.
Outline Responsive Actions in Case of Sickness
Even with excellent prevention, Legionella cases may sporadically occur. Your Legionella Management Plan should outline swift response protocols if you suspect a problem, as detailed in HSG274.
Immediate actions for a potential outbreak include:
- Isolate and shut down suspect water sources. Continue using only after disinfection.
- Collect water samples for Legionella testing.
- Report cases to local PHE health authorities per statutory requirements so they can support investigation and contact tracing.
- Supply health officials with all water system layouts, testing data, maintenance records, etc. to aid the epidemiological response.
- Communicate transparently with occupants about remediation efforts and prevent further exposures.
- Bring in water treatment specialists to conduct emergency disinfections of all water sources.
- Only reopen water systems after thorough retesting proves Legionella eradication.
Though just one illness is concerning, a full-blown Legionnaires’ outbreak can have major consequences. Precautionary planning allows rapid response to protect more people.
Audit Your Legionella Management Plan Regularly for Continuous Improvement
Review and update your Legionella management plan at least every two years as stated in ACoP L8. When major changes are made to water systems, conduct an immediate review to ensure controls stay current.
Schedule regular independent audits by an external water management specialist too. Fresh eyes may catch vulnerabilities you overlooked internally. Use audit findings to target any needed improvements.
Revisit risk assessments frequently as well. Equipment ages, new wings get built, and usage patterns change over time. Continuously evaluate risks and fine-tune your prevention strategy.
Educate Building Occupants on Risk Reduction
Communication shouldn’t end only with your facilities team. Educate all staff and occupants on how you’re ensuring safe water. Post informative signs near sinks and showers. Send regular email updates about your Legionella controls.
Transparency is key. The more informed occupants are, the more confident they will feel using building water systems without fear.
Proper Legionella management requires knowledge, resources, and vigilance. But by making occupant health your top priority, you can develop an effective legionella management plan tailored to your building’s needs that follows UK statutory regulations. Consistency is vital – lapses in control efforts can have rapid consequences. Monitor closely and continually refine as risks evolve. With apt precautions, your water systems can remain secure against Legionella hazards.
What to do next?
Protect your building occupants against the risks of Legionella contamination. Contact Acorn Safety Services today to develop a customised Legionella management plan for your facility that complies with UK regulations. Our team of water treatment experts will assess your systems, identify vulnerabilities, and implement targeted controls to prevent Legionella growth and spread. Don’t wait to take proactive measures – call 01604 930380, email email@example.com or get a quote for your legionella risk assessment.