TRADE association SNIPEF (Scottish and Northern Ireland Plumbing Employers’ Federation) has warned of the dangers of Legionella infection as water systems are restarted in buildings across the country which have been locked down since March.
SNIPEF revealed the potential danger arises from the fact that, during the shutdown, water systems in many buildings – which are designed for constant use – experienced little or no flow, loss of disinfectant residual and tepid-to-warm temperatures.
There are the conditions which allow harmful bacteria such as Legionella to grow.
Like Covid-19, Legionellosis is particularly dangerous to those who are susceptible due to age, illness, immunosuppression or other risk factors, such as smoking.
With more workers returning to the office and the Scottish Government announcing the easing of restrictions on bingo halls, swimming pools and gyms, SNIPEF is warning that ‘comprehensive checks’ must be in place prior to any re-opening.
Martyn Raine, technical and skills manager at SNIPEF said, “Water, as a risk, can often be overlooked. People are very conscious of the dangers of elements such as gas and carbon monoxide, but we have to remain aware that water can pose a real risk to health also. Legionella bacteria can be naturally present in many water sources and systems, and remains dormant below 20oC.
“During lockdown many water systems may not have been in full operation due to building closure. Water systems are designed to be used and operated and not to sit dormant for long periods, if the water system does not turnover there is a real risk of the water being exposed to conditions that may promote bacterial growth.
“It is extremely important to risk assess water systems as buildings open up for business again, but the fact is that it is important all the time and building owners have a duty of care to the occupants, from the private rented sector of homes to larger commercial type buildings such as an office building.”
Raine highlighted the need to review your water system risk assessment that provides a broad overview of the water system and any control measures required.
He said, “SNIPEF member companies are used to carrying out risk assessments which check the water system for any feature, fault or condition that may contribute to an environment which promotes bacterial growth. A risk assessment will identify any control measures and monitoring required on such things storage vessels which could hold deposits of debris or sediments which can act as a catalyst and create a perfect breeding ground for the Legionella bacteria.
“Temperature checks are also essential, since the bacteria thrives between 20oC and 50oC. Therefore, cold water temperatures must be below 20oC and hot water should be stored at 60oC, which kills off the bacteria.”
Other control measures may include cleaning and descaling taps and shower heads, draining down and refilling cold water systems or flushing through with very hot water to disinfect. Plumbers can also check ‘dead legs’, or lengths of pipe where water may lie unused and stagnate.
Raine added, “Duty holders must refer to their water risk assessment which will identify what control measures should be in place as part of normal health and safety procedures, but as we bring unused buildings back into active service, there may also be a need to update your current water risk assessment to address any future building closures. it is vitally important to have qualified, specialist help to create a water risk assessment to make sure that everyone remains safe.”