Summer Heatwaves & Legionella: A Silent Risk for Building Owners
With the UK experiencing a heatwave this week, attention often turns to sun safety, hydration, and keeping buildings cool. But one risk that frequently flies under the radar during hot weather is Legionella — the bacteria that causes Legionnaires’ disease, a potentially fatal form of pneumonia.
Why Summer Heat Increases Legionella Risk
Legionella bacteria thrive in stagnant or slow-moving water stored at temperatures between 20°C and 45°C — conditions that become more likely during hot weather, especially in underused or poorly maintained systems. Increased ambient temperatures can:-
- Warm up cold water storage tanks and pipework.
- Encourage water stagnation in rarely used outlets (e.g., showers in seasonal buildings).
- Exacerbate biofilm growth within pipework, providing nutrients for Legionella.
According to the Legionella Control Association (LCA) — of which The Testing Lab PLC are a registered service provider — it is vital that duty holders, such as landlords & facility managers, understand how environmental changes, including rising temperatures, can increase risk.
“During the warmer months, building owners and facility managers must remain especially vigilant with their water systems. Water systems that are not regularly flushed or maintained can become a breeding ground for Legionella.“— Legionella Control Association guidance, 2023
Who Is Most at Risk?
- Facilities managers of commercial buildings with large hot and cold water systems.
- Landlords with vacant or infrequently used properties.
- Hotels, gyms, and leisure centres, where showers and spas may see uneven use.
- Schools and offices approaching summer shutdowns.
- Care homes and hospitals, where occupants are particularly vulnerable.
What Should You Be Doing Right Now?
With temperatures rising, proactive checks and actions can prevent an outbreak. These include:
- Flushing all little-used outlets at least weekly.
- Monitoring and recording water temperatures at key points in the system.
- Cleaning and descaling showerheads and taps regularly.
- Checking that cold water is stored below 20°C and hot water above 50°C.
- Conducting a Legionella risk assessment if your system hasn’t been reviewed recently.
At The Testing Lab PLC, we help clients across the UK stay compliant and protect public health through:-
- LCA accredited Legionella sampling and laboratory testing
- Legionella risk assessments (in line with HSE’s ACoP L8 and HSG274 guidance)
- Ongoing compliance monitoring and advice
Don’t Let the Heatwave Catch You Off Guard
Legionnaires’ disease cases tend to rise during the summer months. Now is the time to ensure your water systems are safe, compliant, and being proactively managed.
For peace of mind during this heatwave, speak to The Testing Lab PLC about a Legionella risk assessment or testing service.
Contact us for free, expert advice on: 0800 177 7264 or email info@thetestinglab.eu
Alternatively, click the button to Request A Call Back and a member of our team will be in touch.
