Legionella and Water Safety Guidance for the Construction Industry
This water safety article provides guidance covering the control and prevention of legionella and other water safety risks associated with demolition and construction projects.
The guidance looks at what can be done, and how these risks can be mitigated to keep workers and others safe from exposure to legionella and other waterborne bacteria, and the effects of the potentially life threatening condition, Legionnaires’ disease.
A version of this story dealing with guidance for the construction industry on legionella and water safety issues first appeared in Legionella Control International’s newsletter. To get it in your inbox, sign up for free here.
Managing water safety during demolition and construction projects
Construction isn’t just about building new structures from the ground up. It’s also about demolition, building extensions, refurbishments, re-modelling, fit-outs and building maintenance works.
While it is always vital to understand the risks associated with water systems that those working in the construction industry can become exposed to, it becomes even more important when considering working situations involving existing and older water systems. For example, an old building being refurbished for a change of use could well have an increased risk of Legionella bacteria inside the existing pipes and other parts of the water system. This could present a significant risk to those working on-site, and holds true even if the building hasn’t been used in a long time.
The assess, control, and review approach to construction risks
The assess, control, and review approach is a recognised three-step model developed by the Health and Safety Executive (HSE) and is designed to protect those working on construction projects that may involve old, neglected, or disused water systems. Even when some degree of maintenance is present, it may not be sufficient to inhibit those risks associated with legionella bacteria.
Assessing building water systems for legionella risks
Assessing water systems for legionella risk initially involves considering where the risks are in the systems present in the building. Even if the building is set to be demolished rather than refurbished, this step is still necessary. If legionella has been allowed to colonise the existing water systems and the building is demolished without considering this aspect, it could disperse bacteria into the air over a wide distance. This in turn may put those on-site and in the surrounding area at risk of inhaling the dispersed aerosol which may be contaminated with dangerous bacteria.
Legionella bacteria loves to multiply between the temperatures of 20-45 degrees Celsius
Since legionella can cause Legionnaires’ disease, a serious form of pneumonia, the risks associated with such construction or demolition work must be reduced as far as possible. Stagnant water, redundant pipework or similar features, and any sludge or other matter in pipes and elsewhere around the system could present a greater risk. Care should also be taken to protect those workers who fall into the higher risk groups for Legionnaires’ disease. They may be over 50 or have certain health conditions that put them at greater risk, for example.
Controlling water safety risk should focus on prevention
Before any construction or demolition project gets underway, various steps identified during the risk assessment stage should be put into action. For example, carefully draining the water systems present on site removes much of the risk. It could be that one or two outlets, such as a sink, tap, or toilet, are still required on site. It may be possible to limit the water supply to these and drain the remainder, thereby removing risks from elsewhere yet keeping the services needed during the construction or demolition works.
Legionella bacteria loves to multiply between the temperatures of 20-45 degrees Celsius. Therefore, water should be kept above this temperature for hot water and storage purposes, and below for cold water supplies. In some cases, regular dosing with special chemicals (biocides) can help to keep levels of legionella bacteria within safe limits.
Stagnation of water can sometimes create a bigger risk in such circumstances than in a building that is in regular use. Let’s assume construction work is about to begin in a disused building being converted for new owners, for example. In this case, care must be taken to remove the risks associated with the unused water systems (and stagnant water) before construction work begins.
You can see that prevention is a key tool in helping those involved in the building or demolition process keep people safe from exposure to legionella and other waterborne bacteria.
Construction is one of the riskier industries to work in, yet few would consider legionella bacteria as the biggest threat. Fortunately, it is a potential threat that can be mitigated ahead of time, especially when the Assess, Control, and Review model highlighted above is applied correctly.
Reviewing the construction or demolition process for legionella risks
Whoever oversees the construction or demolition process must be aware of the steps required to mitigate as many risks as possible associated with the spread of, and exposure to legionella bacteria. It’s also essential to know the signs of Legionnaires’ disease, so you’re aware of them if they occur among those working on site. Spotting such signs at an early stage could prevent others from catching it and limit the effects of an outbreak.
Fortunately, though, the assess and control stages of monitoring a construction project or demolition job usually prove strong enough to prevent such an outbreak. Legionella bacteria can also cause Pontiac fever, a less serious yet still notable disease. Prevention of such cases in these potentially risky situations is always the aim.
Considering outside water safety assistance
We can see that in the construction industry, working in abandoned or older buildings and renovating them for further use is very different to working on new construction projects. As such, there are specific requirements and needs concerning safety around a water system that need to be considered.
Therefore, it may be prudent in some situations to consider seeking help from experts such as Legionella Control International. While responsibility remains with those in charge of the project, seeking an experienced legionella expert to conduct a risk review of your next construction or demolition project could be easier, safer and more thorough in many cases.
Expert legionella risk management for the construction sector
Legionella Control International is a world-leading legionella and water safety specialist. Our teams of experts support building design and construction professionals, and those responsible for workplace safety.
We will help you to protect your workers, customers and others in meeting your health and safety obligations in this specialist area.
We deliver a range of specialist risk management solutions including risk assessment, design review, regulatory compliance auditing, specialist legionella training, water quality analysis and other services that help keep people safe.
If you would like to speak with one of our legionella specialists about managing your water safety risk call us today on 0330 223 36 86 or contact us here …
