When outlets, taps or showers are not used often the associated water inside the pipes and tanks doesn’t move and this still water can become dangerous. One big problem is Legionella bacteria. If these bacteria grow, they can cause Legionnaires’ disease, a serious illness. That’s why flushing your water system is so important. It helps stop Legionella from spreading. At Comfort Services Group, we support care homes, schools, offices, and other sites with proper flushing routines. It’s one of the best ways to stay safe.
What is Water Flushing?
Water flushing is the process of running water through taps, showers, and other outlets to keep it moving. This helps remove stagnant water from the system. It also helps maintain the right hot and cold water temperatures. When we flush a water outlet, we make sure old water is pushed out. That way, fresh water comes in. This regular flushing is a simple but powerful step to reduce the risk of Legionella. It’s especially important in buildings with infrequently used areas.
How Does Water Flushing Work?
Water flushing works by turning on each outlet long enough to pull fresh water through the pipes. This includes flushing taps, showers, and any other water outlet that hasn’t been used recently. In most cases, each flush should last at least five minutes. It’s important to flush both hot and cold water systems. By moving water through the system, we reduce the chance for bacteria to grow. This flushing regime must happen at least weekly or even more often if needed.
- Disrupting the biofilm
Biofilm is a slimy layer that can build up inside pipes. Legionella bacteria can hide and grow in this biofilm. When water sits still, the biofilm gets thicker. But when we flush the system, we disturb that layer. Flushing helps break it apart. This makes it harder for the bacteria to survive. Disrupting biofilm is one reason Legionella flushing is so important. If we don’t flush, that film stays undisturbed, and Legionella risk goes up.
- Maintaining water temperature
Legionella bacteria grow best in warm water, between 20°C and 45°C. So, keeping water temperatures outside this range helps control Legionella. Flushing helps achieve this by clearing out cold spots or warm areas in the system. When water sits, the temperature can fall into that danger zone. By regularly flushing hot and cold outlets, we help maintain safe water temperature. It’s a key part of water safety. And it’s something we check during a Legionella risk assessment.
- Preventing stagnation
Stagnant water is water that doesn’t move. This happens in pipes, tanks, and outlets that are not used often. And it’s a big problem because stagnant water gives Legionella bacteria time to grow. Regular flushing prevents stagnation by keeping water flowing. Even just a weekly flush makes a big difference. When we visit sites, we often find that infrequently used taps or showers are the most at risk. A proper flushing regime keeps all water fresh and moving.
- Removing sediment and deposits
Over time, sediment and scale can build up in a water system. These deposits can trap bacteria like Legionella. They also affect water flow and can damage the system. Regular flushing helps remove these unwanted bits. It keeps the pipes cleaner and more efficient. When we flush, we push out anything that has settled in the pipes. It’s one way to reduce the risk of Legionella and keep the system in good shape. Don’t ignore this simple task—it matters.
Water Flushing Compared to Other Methods of Preventing Legionella Bacteria
Water flushing is one of many tools to control Legionella. But it’s often the first line of defence. Compared to chemical dosing or thermal treatment, flushing is quick, low-cost, and easy to carry out. It doesn’t replace full water treatment, but it supports it well. Infrequently used outlets benefit most. While some methods kill bacteria, flushing helps stop them from growing in the first place. That’s why we always include it in a full water safety plan.
Key Reasons Water Flushing is Critical
Water flushing does more than just move water. It plays a big role in health, safety, and maintenance. It helps stop the growth of Legionella, clears pipes of debris, and keeps hot and cold water at the right temperatures. It also shows your site is serious about water safety. If you’re responsible for a building, especially one with vulnerable people, flushing is not optional. It’s a simple step that helps you comply with your Legionella risk assessment.
- Age and condition of the system
Older water systems are more likely to have problems. Pipes may be corroded, and sediment builds up faster. These conditions are perfect for the growth of Legionella. Flushing helps slow this down by keeping water fresh and pipes cleaner. Even new systems need regular flushing—age isn’t the only factor. But older systems especially benefit from weekly flushing to reduce the risk of Legionella. At Comfort Services Group, we assess each system to find the best plan.
- Water quality issues
Poor water quality means more nutrients for bacteria. If your water system has iron, scale, or organic matter, it creates food for Legionella. That’s why flushing is helpful. It helps get rid of unwanted substances and replaces them with treated water. It also makes other water treatment steps, like dosing, more effective. If you’re having water quality issues, flushing is a good first step. It’s easy to do and works best when done regularly.
- System inefficiencies
When a water system isn’t working properly, it can create hot and cold spots. These are ideal places for Legionella to grow. A flushing regime helps identify and reduce these problem areas. It also helps balance the system and supports good flow. If flushing takes too long to get hot or cold, it might show a deeper issue. That’s something we can help fix. At Comfort Services Group, we don’t just flush, we look for what’s causing the problem.
Keeping Records of Your Legionella Flushing Programme
Keeping records is key to showing that your Legionella control measures are working. Every time you flush a water outlet, you should record the date, time, and name of the person who did it. You should also note the water temperature, if possible. These records are important during a Legionella risk assessment. They show you’re taking action. Without them, you can’t prove that regular flushing is happening. We always help our clients set up easy-to-follow record systems.
The Importance of Training and Expertise when Flushing
Flushing sounds simple, but doing it the wrong way can be risky. If the outlet splashes or sprays, it can release bacteria into the air. That’s why proper training is essential. Staff need to know how to flush safely and correctly. At Comfort Services Group, we train teams to carry out flushing safely. We also check that every used outlet is being handled right. Expertise helps keep everyone safe, and that’s the goal.
Regular Flushing to Control Legionella in Empty Properties
Empty buildings are high risk for Legionella. Water sits still for weeks or months. That creates perfect conditions for bacteria. Regular flushing during these times is critical. It keeps water moving and helps reduce the risk of Legionella. Whether it’s a care home, school, or office, flushing needs to be done weekly at least. If the property will be closed for long, you might need a full water treatment plan. We help make sure nothing is left to chance.
The Five-minute Flush
One of the easiest ways to minimise the risk is the five-minute flush. This means running each infrequently used outlet for five minutes. It helps pull fresh water into the system and push out the old. This should be done at least weekly. If you’re flushing showers, don’t forget to remove the head first to stop splash and spray. It’s a quick step that goes a long way in protecting water safety.
It’s important to remember that your hot and cold water temperatures should achieve the following:
- Hot water
Hot water should reach at least 50°C within one minute of running from the tap. This high temperature helps kill Legionella bacteria. If it doesn’t reach this level, it could be a sign of a system problem. We check this often during our site visits. The water tank should also hold hot water at 60°C or more to control Legionella properly.
- Cold water
Cold water should stay below 20°C. This keeps the water too cool for Legionella to grow. If the cold water is above 20°C, especially after a minute of running, something could be wrong. Maybe the pipes are near a heat source. Or there’s no insulation. Cold water checks are a simple way to protect your system.
When Flushing, Remember to Guard Against Splashing Water
When flushing taps or showers, don’t let water spray or splash. This can send droplets into the air. If Legionella bacteria are present, they can be breathed in. That’s how people get sick. Always flush outlets gently. Use a cloth to cover the tap, or remove the shower head. Make sure the room is well-ventilated. Safety comes first. That’s something we always remind staff when we provide flushing training.
Why is Water Flushing Crucial for Legionella Prevention?
Flushing keeps water moving. It helps remove bacteria, dirt, and biofilm. It protects hot and cold water systems from becoming unsafe. Without flushing, water becomes stagnant, and that’s when Legionella risk rises. Legionnaires’ disease is serious. And often preventable. Regular flushing is one of the easiest ways to reduce the risk of Legionella. That’s why we always recommend it as part of a complete water safety plan.
Trusted Experts in Legionella Control and Water Safety
At Comfort Services Group, we’ve worked across the UK to help care homes, schools, offices, and more keep their water safe. We understand how to control Legionella with practical, proven steps. Our team helps with flushing, training, water treatment, and risk assessment. We don’t just meet the rules, we help you stay ahead of them. Safe water matters. And we’re here to help you make sure it stays that way.
FAQs
Is flushing proven to mitigate Legionella and prevent Legionnaires’ Disease?
Yes, flushing is a proven way to reduce the risk of Legionella. By keeping water moving and maintaining proper hot and cold temperatures, flushing helps prevent the bacteria from growing. It’s especially helpful in infrequently used outlets. While it doesn’t replace other treatments, it works well when done regularly and properly, as part of a full Legionella control plan.
How to identify water outlets that need regular flushing?
Look for taps, showers, or other outlets that are not used every day. These are known as infrequently used outlets. Areas like spare bathrooms, storage rooms with sinks, or unused staff rooms often have these. A good flushing regime will include all of these. During our visits, we help you list and track each outlet so nothing gets missed.
Who is responsible to identify unused outlets?
The duty holder or building manager is usually responsible. They must make sure a proper Legionella risk assessment is done. Part of that includes identifying infrequently used outlets. Once these are known, a flushing schedule can be created. Our team at Comfort Services Group often supports this process to make it easy and clear for everyone involved.
Should some outlets be flushed more than others?
Yes, outlets that are used less often should be flushed more regularly. Some might need flushing every day. Others may only need weekly checks. The key is how often the water outlet is used. The less it’s used, the higher the risk of Legionella. That’s why a tailored flushing regime is so important. We help our clients get it right.
What does the Health & Safety Executive say about flushing?
The Health & Safety Executive (HSE) advises that water outlets not used at least weekly should be flushed. This is part of controlling the risk of Legionella. They recommend a clear schedule and proper records. The HSE also says that flushing is just one part of the bigger water safety plan. Comfort Services Group follows all these guidelines when helping clients with their systems.
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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