Understanding Legionella: Why Regular Testing is Crucial for Building Owners

June 26, 2023

Background

Legionella, the bacterium behind Legionnaires' disease, a severe form of pneumonia, can grow in human-made water systems. This potentially fatal disease spreads when individuals inhale water droplets containing the bacteria.

There have been several notable cases of Legionnaires' disease outbreaks in the UK:

Edinburgh Outbreak in 2012: One of the most significant recent outbreaks of Legionnaires' disease in the UK happened in Edinburgh, Scotland, in June 2012. Over 100 suspected cases were reported, and four people died. The outbreak was traced back to a cooling tower in the city's industrial area, and several companies were investigated over the outbreak.

Stoke-on-Trent Outbreak in 2012: Later in the same year, another outbreak occurred in Stoke-on-Trent. This outbreak resulted in two deaths, and 19 people were confirmed to have contracted the disease. It was also traced back to a cooling tower, which was not being adequately maintained.

Barrow-in-Furness Outbreak in 2002: This was the UK's worst outbreak, with seven deaths and 180 people infected. A company was fined £1 million as they had failed to adequately manage and maintain their air conditioning system.

Legionella in Buildings

In building environments, particularly those with intricate water systems, Legionella can thrive. Key hotspots include air conditioning systems, hot water tanks, plumbing systems, and facilities like hot tubs and decorative fountains.

Legal Obligations in the UK

In the UK, landlords and building owners are required by the Health and Safety Executive (HSE) to assess and control Legionella risk. While there's no rigid rule on the frequency of Legionella testing, it's recommended to perform an annual test, especially if changes have been made to the water system or Legionella has previously been detected.

Tips for Reducing Risk

To minimise Legionella risk, the following areas can be key;

Risk Assessment: Regular risk assessment is the first step to reduce Legionella risk. It includes identifying potential sources of Legionella, assessing the risks, and implementing measures to control them.

Water System Maintenance: Keep all water systems clean and treated where necessary, especially those that may produce aerosols. Regularly disinfect and descale showers and taps.

Temperature Control: Legionella thrives in lukewarm water. So, keep cold water cold (below 20°C) and hot water hot (above 50°C).

Regular Testing: Regular Legionella testing is crucial, preferably annually, to ensure the measures put in place are working.

By understanding Legionella, how it spreads, and the importance of regular testing, we can together prevent outbreaks of Legionnaires' disease. This not only helps us comply with UK laws and regulations but also ensures the health

For more information visit our Legionella Testing page, or the HSE Legionella and legionnaires' disease page.

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Do New Electrical Appliances Really Need PAT Testing?

September 9, 2025

Introduction We’ve been hearing this question more and more from customers lately: “Do brand-new appliances still need PAT testing?” It’s a fair question. After all, new equipment usually arrives sealed, with manufacturer labels and testing certificates. But when it comes to safety, compliance, and peace of mind, the answer is a little more nuanced. What the Law Actually Says There is no strict legal requirement that says every appliance must be PAT tested. The law simply requires that employers and duty holders keep electrical equipment safe and properly maintained. That means the responsibility is on you to ensure equipment is safe to use, whether it’s new or not. The law doesn’t prescribe how you do it, but PAT testing is one of the most reliable methods. New Equipment: What Best Practice Looks Like Industry guidance generally states that brand-new equipment does not usually need a full PAT test . A thorough visual inspection is often enough. Why? Because new appliances are supplied as safe. But… there are a few important caveats. Why Some Organisations Still Choose to PAT Test New Appliances Even new items can develop issues before they reach you: Transit damage : knocks, drops, or rough handling. Storage conditions : damp, dust, or stacking problems. Manufacturing faults : rare, but possible. For most offices or low-risk workplaces, a visual check may be sufficient. But in higher-risk environments, like healthcare, construction, or manufacturing, many duty holders choose to test new equipment anyway. It’s about risk, peace of mind, and protecting people. A Risk-Based Approach That Works Low-risk settings (offices, shops, classrooms): Carry out a visual inspection, log the equipment, and move it into service. High-risk or critical settings (workshops, hospitals, factories): Consider a full PAT test even for new appliances, to establish a safe baseline and prevent costly downtime or accidents. Documentation and Competence Matter Whether you perform a visual inspection or a full PAT test, keep a record. This creates a clear audit trail and shows that you’ve taken reasonable steps to ensure safety. It’s also important that the person carrying out the inspection or test is competent, trained, knowledgeable, and confident in spotting issues. Conclusion: What’s the Smartest Strategy? In most cases, new appliances don’t require PAT testing, just a solid visual check as part of your risk management process. But remember: if the equipment is critical, the environment is high-risk, or there’s any sign of damage, a PAT test is a small investment in safety and peace of mind.