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Legionella: the real risks in your heating and hot water system

There’s been a spot of bother for one of the anchors on Fox News in the USA this week. He claimed that he hadn’t washed his hands for 10 years. ( He then went on to say, “Germs are not a real thing. I can’t see them, therefore they’re not real.” In the face of criticism and derision, he claimed that his comments were a joke. It’s not clear whether or not he was being serious. But there is quite a lot of scientific evidence that bacteria and viruses ARE real. And there are several laws which mean that UK organisations have to protect employees, customers and clients against them.

One bacterium which poses severe safety risks is legionella. It’s a legal duty to protect staff and the wider public against an outbreak of Legionnaire’s disease. Any failure can result in hefty fines – or, in the case of fatalities, could lead to corporate manslaughter charges. In this blog, we take a closer look at how healthcare facilities, industrial plants and leisure centres can limit their risks. And we’ll be discussing how Hodgkinson Bennis can work with you to do so.

The low-down on Legionella

Legionella is a water-borne bacterium that can cause serious illness and even death. Legionella bacteria particularly thrive in the 20-50 degrees Centigrade (oC) range, proliferating in artificial environments where temperatures rise above ambient. The bacteria cause Legionnaire’s disease, which presents as a form of severe pneumonia. In the UK, the latest figures show that 447 cases of legionellosis (including Legionnaire’s disease) were reported during January-August 2018.

Many cases result from travel abroad; typically, in the UK, this accounts for around half of confirmed cases. However, there are a number of potential domestic sources of the bacteria. Healthcare facilities are at particular risk, as pre-existing medical conditions increase the chances of contracting the disease, with higher mortality. Engineered water systems at industrial plants such as condensers can harbour the bacteria. And legionellae can also proliferate in air-conditioning systems or at spas with hot tubs, where they become airborne in water droplets.

If you’re a facilities manager, chances are you’re familiar with the UK’s Health & Safety Executive (HSE). It publishes guidance for businesses and landlords on the subject of legionella (Read the advice here> And it’s responsible for prosecuting organisations which fail in their legal duty to protect against legionella. One recent case was a £27k fine in December 2018 for Tendring District Council in Essex. The case centred on a man who died, having contracted Legionnaire’s disease in a shower at a leisure centre in 2016. Here are some of the main ways in which organisations can protect against the risks posed by legionella.

The right equipment can control Legionella

Systems at facilities such as hospitals and hotels often do store hot water, to cope with fluctuating demand throughout the day. To mitigate legionella risks, such systems should maintain the hot water temperature at a minimum of 60oC. Meanwhile, another potential source of legionellae is stagnant air conditioning units. (This is often a seasonal problem during the winter, when aircon is not required). To make sure the system doesn’t harbour legionella, facilities managers need to ensure adequate treatment through disinfection or permanent chlorination.

Facilities which use a calorifier, such as industrial plant, could be at greater risk of legionella. Calorifiers use a heat transfer coil, in which steam is used to heat large quantities of water. In contrast, a packaged plate heat exchanger could limit limit risks associated with legionella. It’s smaller than an average calorifier and delivers hot water instantaneously, thereby reducing a plant’s reliance on stored water.

Staff training to stay on top of Legionella

Legionella awareness training should be an essential for staff involved in operating boiler and cooling plant. Learners should come away with an understanding of risks, how to control them and warning signs to look for in areas where bacteria can replicate. Employee vigilance can then be the first line of defence in battling legionella. Training providers include Develop Training (which has good downloadable resources on legionella), while others offer online courses.

Annual inspections limit Legionella risk

One vital element for any manufacturing facility using steam is the annual insurance inspection. Hodgkinson Bennis can carry such inspections out with the minimum of disruption to your operations. We’ll always check the vessel’s condition, focusing pressure levels in the vessel and welds in particular. We’ll drain standard older-model calorifiers and remove the heat transfer coil for closer inspection. The inspection process for a packaged plate heat exchanger is more straightforward; plates can be checked by simply sliding them out of the unit’s frame. Meanwhile, regular inspection of all boiler equipment is equally as important at other facilities, such as hospitals and hotels.

Pipework maintenance is vital too

Just as important as the boiler itself, a system’s pipework must be properly maintained. Hodgkinson Bennis can rationalise your organisation’s pipework, which can be a great way to limit the risks of legionella. We’ll remove dead and blind ends, where temperatures in the hot-water system can fall into the range 20-50oC. Or we can install more point-of-use heaters, with less complicated distribution pipework.

Contact one of the team today to find out more about all of our services for industrial and commercial boilers – and how we can limit your legionella risks.

Call: 0161 790 4411

About Hodgkinson Bennis

Hodgkinson Bennis design, install and maintain the most fuel-efficient commercial and industrial boilers for biomass and fossil fuels. Headquartered in Manchester, we work across the UK, particularly in the North West, North East and throughout the Midlands. Contact us today to discuss how we can deliver advanced commercial and industrial boilers.

At Hodgkinson Bennis, we have worked with commercial and industrial boilers since 1872. This history gives us an enviable amount of experience as pioneers in the industry. We place an enormous emphasis on ensuring the health and safety of all team members, suppliers, contractors, and the public. As well as the most fuel-efficient boiler solutions for industrial and commercial applications, Hodgkinson Bennis offer help with public-sector engineering projects.


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