Speak To An Expert
Get clear, personalised advice for your situation.
Jot down a few questions to make the most of your conversation.
What causes Legionnaires' disease?
Legionnaires' disease is a serious lung infection caused by inhaling tiny droplets of water contaminated with Legionella bacteria. It is not spread from person to person. The bacteria can grow in man-made water systems if conditions are right.
In the UK, the main risk is poorly maintained water systems in buildings such as hotels, hospitals, offices, leisure centres and care homes. Warm water, stagnant water and areas where scale or sludge build up can all help the bacteria multiply.
How can buildings reduce the risk?
Good water management is the most important way to prevent Legionnaires' disease. Building owners and landlords should carry out a risk assessment and put a control plan in place. This should be reviewed regularly, especially after changes to the system or building use.
Water systems should be kept clean and properly maintained. This includes flushing infrequently used outlets, preventing water from sitting still for long periods, and making sure hot water is stored and distributed at the right temperature. Cold water should also be kept cold enough to limit bacterial growth.
Why maintenance matters
Regular inspection and maintenance help stop Legionella from building up in tanks, pipework, taps and showerheads. Descaling and disinfecting components can be important where limescale or rust has formed. Filters, cooling towers and spa pools need especially careful attention.
Professional advice is often needed for larger or more complex systems. In workplaces and commercial settings, staff should be trained to understand the risks and follow the control measures properly. Keeping clear records of checks and cleaning is also good practice.
What can households do?
Most homes are low risk, but basic precautions still help. If a shower or tap has not been used for a while, run it for a few minutes before using it. This is especially sensible after holidays or when returning to a property that has been empty.
Householders should also keep showerheads and taps clean and free from scale. If a home has a hot water system, it should be serviced according to the manufacturer’s instructions. People with concerns about a private water system can seek advice from a qualified plumber or water hygiene specialist.
Who is most at risk?
Older adults, smokers, and people with weakened immune systems are more likely to become seriously ill if exposed. Those with long-term health conditions may also be at higher risk. Extra care should be taken in hospitals, care settings and other places where vulnerable people stay.
If someone develops flu-like symptoms, a cough, fever or shortness of breath after being in a building with water systems or a spa pool, they should seek medical advice promptly. Early diagnosis and treatment can make a big difference.
Frequently Asked Questions
Legionnaires' Disease prevention refers to the practices used to reduce the growth and spread of Legionella bacteria in building water systems. It is important because Legionella can cause severe pneumonia, especially in older adults, smokers, and people with weakened immune systems.
Legionnaires' Disease prevention works by controlling conditions that allow Legionella to grow, such as warm stagnant water, scale, and sediment. Common methods include maintaining proper water temperatures, flushing infrequently used outlets, cleaning systems, and disinfecting water equipment.
The building owner or operator is usually responsible for Legionnaires' Disease prevention in a commercial building. They may also rely on facility managers, maintenance staff, and water treatment professionals to implement and monitor a water management program.
The most effective steps for Legionnaires' Disease prevention in hotels include maintaining hot water temperatures appropriately, regularly flushing guest rooms that are unused, cleaning showerheads and faucets, monitoring cooling towers, and keeping a documented water management plan.
Homeowners can support Legionnaires' Disease prevention by keeping hot water heaters properly maintained, flushing seldom-used taps, cleaning showerheads, and preventing stagnant water in plumbing. Home systems generally pose a lower risk than large building systems, but basic maintenance still helps.
For Legionnaires' Disease prevention, hot water should be kept hot enough to discourage bacterial growth and cold water should remain cold. In many guidance documents, hot water storage is kept at or above 60°C (140°F) and distribution temperatures are managed carefully to reduce scalding risk while limiting Legionella growth.
Stagnant water is a risk in Legionnaires' Disease prevention because Legionella bacteria can multiply in water that is not moving, especially when temperatures are favorable and nutrients are present. Flushing unused fixtures and removing dead legs in piping help reduce this risk.
Water systems should be inspected regularly as part of Legionnaires' Disease prevention, with frequency depending on the system type and risk level. Many facilities use routine checks, seasonal reviews, and periodic comprehensive assessments to verify temperatures, disinfectant levels, and equipment condition.
A water management program for Legionnaires' Disease prevention is a structured plan that identifies where Legionella could grow and spread, sets control measures, and defines monitoring and corrective actions. It usually includes system mapping, temperature monitoring, maintenance schedules, and documentation.
Cooling tower maintenance is critical for Legionnaires' Disease prevention because towers can generate aerosols that may spread Legionella if the system is contaminated. Proper maintenance includes cleaning, disinfecting, controlling biofilm, and regularly inspecting drift eliminators and water treatment systems.
Disinfection plays a major role in Legionnaires' Disease prevention by reducing or eliminating Legionella in water systems. Methods may include chlorination, monochloramine, chlorine dioxide, or other approved treatments, chosen based on the system and local regulations.
Hospitals can improve Legionnaires' Disease prevention by using rigorous water management, temperature control, point-of-use filtration in high-risk areas, and frequent testing where appropriate. Because patients may be highly vulnerable, healthcare facilities often apply stricter controls than ordinary buildings.
Common warning signs that Legionnaires' Disease prevention measures may be failing include persistently low disinfectant levels, inconsistent water temperatures, visible sediment or scale, biofilm buildup, and positive Legionella test results. These signs indicate that corrective action may be needed.
Flushing unused outlets helps Legionnaires' Disease prevention by replacing stagnant water with fresh water, which can reduce bacterial growth and lower the chance of aerosolizing contaminated water. This is especially useful in guest rooms, vacant offices, and seasonal facilities.
Legionnaires' Disease prevention can significantly reduce risk, but it cannot guarantee complete elimination of Legionella. The goal is to keep bacteria at very low levels and minimize exposure through consistent maintenance, monitoring, and prompt correction of problems.
Buildings that need Legionnaires' Disease prevention measures most urgently include hospitals, nursing homes, hotels, apartment complexes, schools, gyms, and large office buildings. Any facility with complex water systems, warm water, aerosol-generating equipment, or vulnerable occupants should prioritize prevention.
Water features such as decorative fountains, spas, and misting devices can complicate Legionnaires' Disease prevention because they may aerosolize water and support bacterial growth if not maintained properly. Regular cleaning, disinfection, and water-quality monitoring are essential.
Testing used for Legionnaires' Disease prevention may include Legionella culture or polymerase chain reaction testing, along with routine checks of temperature, disinfectant residual, pH, and turbidity. Testing helps verify whether control measures are working and whether corrective actions are needed.
Staff can be trained for Legionnaires' Disease prevention by teaching them how Legionella spreads, how to follow the water management plan, how to document inspections, and how to respond to abnormal readings or positive test results. Training should be repeated regularly and updated when systems change.
Professional help should be sought for Legionnaires' Disease prevention when a building has complex plumbing, cooling towers, repeated water quality issues, or a positive Legionella result. Certified water treatment specialists, industrial hygienists, or environmental health professionals can help assess risk and implement controls.
Ergsy Search Results
This website offers general information and is not a substitute for professional advice.
Always seek guidance from qualified professionals.
If you have any medical concerns or need urgent help, contact a healthcare professional or emergency services immediately.
Some of this content was generated with AI assistance. We've done our best to keep it accurate, helpful, and human-friendly.
- Ergsy carefully checks the information in the videos we provide here.
- Videos shown by Youtube after a video has completed, have NOT been reviewed by ERGSY.
- To view, click the arrow in centre of video.
- Most of the videos you find here will have subtitles and/or closed captions available.
- You may need to turn these on, and choose your preferred language.
- Go to the video you'd like to watch.
- If closed captions (CC) are available, settings will be visible on the bottom right of the video player.
- To turn on Captions, click settings.
- To turn off Captions, click settings again.