Is your unoccupied building harbouring legionella bacteria?
As many commercial and residential buildings remain empty over periods of lockdown, experts are concerned that these have the potential for a build-up of legionella bacteria, responsible for Legionnaires’ disease.
Why it happens
Legionella bacteria can grow and multiply in building water systems, particularly when water is left stagnant or tepid, or the system is not regularly used. The illness is then contracted when contaminated water droplets are breathed in.
What are the risks?
Legionnaires’ disease is a serious lung infection and can cause major complications in a small number of cases. If your employees or visitors contract Legionnaires’ disease as a result of your error, your business could be held liable.
While many employers’ liability insurance policies cover this risk, it isn’t standard under public liability insurance. This means that you will need to take out a specific legionella policy to ensure that you’re properly protected.
Protecting your building
Following advice from health and insurance experts to take sound measures to protect your building, we take a look at what you can do now to minimise the risk of a build-up of legionella bacteria.
Choose the right equipment
Dan Martindale, sales director at Andrews Water Heaters, explains: “To minimise the risk of Legionnaires’ disease, [property owners] need to consider the best way to store and distribute hot water throughout the whole system at 60ºC or above so that legionella bacteria cannot survive.
“This starts from the specification of products and components at the design stage of a job. This could mean choosing water heaters with a built-in anti-legionella programme, or measures that increase turbulence to reduce thermal stacking. Tanks designed to prevent cooler ‘layers’ where legionella would be able to thrive should also be considered from the beginning of a project.”
Service your system regularly
Water hygiene issues can be addressed with regular maintenance checks and periodic system cleans. Temperature control is the primary method used to control legionella risk:
- Hot water storage cylinders should store water at 60°C or higher
- Hot water should be distributed at 50°C or higher
- Cold water should be stored and distributed below 20°C
Stagnant water can encourage legionella growth. Make sure to keep pipe routes short with a few dead ends as possible, flush out any infrequently used outlets such as taps and showerheads weekly, and make sure to adequately insulate pipes so water keeps its temperature.
“As we’ve seen with a case of Legionnaires’ disease at a hotel in Ludlow, failure to take preventative measures properly can have catastrophic results,” continues Dan Martindale.
“The possible presence of Legionella bacteria in any part of the hot water system is not a risk that any[one] should take.”
Talk to a member of the team at Lockyers about reviewing your existing cover to ensure you are properly protected against the risks associated with legionella bacteria or call us on 01924 278222.