The safety of your water systems must be taken as seriously as all the other health & safety aspects of your business. This means you need to take steps to protect your employees, visitors, and customers in order to reduce the risks of infection from any waterborne viruses or bacteria such as legionella and E. coli. Otherwise, you could be making an expensive mistake, as Jeremy Clarkson found out last year. He had to remove spring water bottled from the well on his farm after he’d begun selling it in his farm shop once he discovered that the water contained bacteria.

While your business is not legally required to undertake legionella testing, Health & Safety regulations state that you must understand and manage the risks and keep accurate records.

Why is legionella so dangerous?

If it is inhaled, the legionella bacterium has the potential to develop into Legionnaires’ disease. Legionnaires’ is a type of pneumonia that can be fatal, especially among elderly people and people with pre-existing medical conditions. This is why, under the Health and Safety at Work etc Act 1974, duty holders have a responsibility to comply with their legal responsibilities to control legionella bacteria in water systems.

Optimum conditions for legionella bacteria

To be able to control legionella, it’s essential to understand the kind of conditions where it is likely to multiply and thrive. And that is in stagnant water that’s between 20oC and 45oC and has plentiful nutrients such as algae, scale, rust, and sediment.

The bacteria can spread from water to the lungs via devices that produce tiny water droplets that can easily be inhaled, such as showers, spas, hoses, sprinklers, and water-based air conditioning units.

Inside the home, where the water system is used on a daily basis, the risks from legionella are low. Water in the system does not get the opportunity to stagnate, and the temperature of hot water is generally much higher than 45oC. In business premises where water is only needed for bathrooms and kitchens, the risks from legionella will be low as long as the building is in constant use.

Risk assessment after closures

Premises that have been left vacant are therefore more likely to be at risk from legionella, and it is advisable to test the water for legionella and other contaminants before the building is occupied once more. Over the lockdowns, when business premises were closed for months at a time, there were increased risks from water stagnation. The HSE, therefore, advised businesses to review their legionella risk assessment before reopening their premises.

If your premises need to close again for any reason, it’s a good idea to visit once a week to run all the taps for a couple of minutes and flush the toilets to keep the system moving, making it less likely that the system will provide bacteria with the stagnant conditions they thrive in.

Water testing

Under normal circumstances, it is recommended that most businesses only need to test their water systems for legionella every two years. Businesses that cater for the elderly or people with a compromised immune system - such as care homes and medical facilities - need to be tested annually.

If you own or run a business premises, you can book a legionella risk assessment or water test by contacting a professional water hygiene services company. Alternatively, if you run a small business, look out for legionella testing kits that will enable you to save money by taking your own water samples.

If you’d like to find out about our services, or if you’re interested in switching business water retailer, please contact us and speak to one of our advisors.


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