Legionella cleaning and disinfection services
Legionella bacteria multiply quickly when conditions are right. Showers, storage tanks and pipework create the perfect environment for growth, putting your people at risk.
Our Legionella cleaning and disinfection service brings your water system back under control, meets ACoP L8 requirements and gives you confidence that you’re protecting your people, systems and reputation.
When you should disinfect your water system
Your risk assessment and water management plan will guide most decisions, but there are clear situations when cleaning and disinfection become necessary:
- Following inspection findings or evidence of contamination
- After alterations, new pipework installations or a period of low use
- When monitoring results show bacterial counts above acceptable levels
- After a suspected or confirmed case of Legionnaires' disease
Some parts of your water system need more frequent attention than others. Showers and spray taps should be cleaned regularly as part of your ongoing maintenance. For hot and cold water systems, cooling towers and closed circuits, the frequency depends on your risk assessment, water quality results and inspection findings.
All our Legionella cleaning and disinfection work meets ACoP L8, BS 8558, PD 855468:2015 and the Water Supply (Water Quality) Regulations.
Our Legionella disinfection methods
We use thermal or chemical disinfection depending on what’s best for your system. The choice comes down to your risk assessment findings, the type of installation, the level of contamination and how the building operates.
- Thermal disinfection involves raising water temperatures to levels that kill Legionella bacteria. The bacteria multiply between 20°C and 45°C, begin to die off at around 60°C and are killed almost instantly at 70°C. We heat the system and flush through every outlet to ensure thorough treatment. It's a proven method that works well for most hot and cold water systems.
- Chemical disinfection offers an effective alternative when thermal treatment isn’t practical. We use approved biocides, such as sodium hypochlorite (with sodium thiosulphate neutralisation) and silver-stabilised hydrogen peroxide, selected to suit the system and its application. Our processes ensure effective disinfection, correct contact times and safe handling throughout, while protecting pipework and components from damage.
- Cleaning and maintenance go hand in hand with disinfection. As part of any cleaning and disinfection process, strainers and filtration components are inspected and cleared to ensure the system is fully disinfected, running efficiently and completely compliant.
Our engineers are fully trained and experienced in protecting your system during treatment. We guard against airlocks, ensure even distribution across the pipework and give treatments the time they need to work effectively.
What to expect: step-by-step procedure
We plan and deliver treatment so it’s effective, compliant and as low-disruption as possible.
- Assessment and planning: Our engineers assess the system, agree the best approach and schedule the work to minimise disruption.
- Preparation: As part of the process, tanks, outlets and other components are cleaned to make sure the treatment reaches every part of the system. Pipework is also checked for dead legs or dead ends, so all areas are open, accessible and properly disinfected.
- Disinfection: We apply thermal or chemical treatment under controlled conditions. Our processes protect pipework and fittings while ensuring effective coverage across the whole system.
- Flushing and return to service: Once treatment is complete, we flush the system and bring it safely back into service. We check pressure and flow rates to confirm normal operation, and where your risk assessment requires it, we can take water samples to verify the results.
You’ll receive full documentation of the work, along with recommendations for ongoing monitoring. If you need support with temperature checks, sampling schedules or remote monitoring, our team can guide you on the right approach for your site.
Why Aquatrust?
- Experienced engineers: decades of practical experience, approachable and thorough on every job.
- Proven compliance: ISO 9001:2015 certified and members of the Legionella Control Association. We hold all the required accreditations to operate safely in water compliance – find out more about our accreditations and memberships.
- End-to-end support: Disinfection is just one part of what we do. Our services also include risk assessments, routine monitoring, remedial works, training and remote water monitoring.
- Minimal disruption: We plan carefully and work efficiently so treatments cause as little disruption as possible.
- Strong team culture: We're a close-knit team focused on teamwork, long-term relationships and doing right by our clients.
FAQs
Keeping systems safe and compliant
Our Legionella cleaning and disinfection service restores your water quality, protects your site and people and gives you the compliance documentation you need.
Whether you’re responding to inspection findings, bringing a system back online or managing an increased risk, our experienced engineers are here to help.
