Locked down but not forgotten

16th April 2020

Don’t ignore essential legionella treatment in abandoned buildings

The COVID 19 crisis has left UK businesses in a state of limbo with the advice to work from home where possible. Many commercial buildings now lie empty and the return of people is not likely for a number of weeks.

When it comes to the water systems within these buildings, this lack of usage could cause potential legionella and corrosion issues if water is left to stagnate; issues that will only get worse as we move into the warmer summer months. In fact, a legionella water treatment regime is on the government’s list of essential services. This highlights the importance of keeping up this part of building maintenance.

If left unchecked, FMs, building managers and occupants will return to buildings with a heightened risk of legionnaire’s disease. In addition, pipework and associated systems may be more likely to need repairs and/or breakdown.

Not only must buildings keep up their existing water treatment regime – such as monthly temperature monitoring and six monthly tank inspections – it may be that maintenance regimes need adjusting to account for the lack of usage. These adjustments could include:

Increased flushing:

  • With reduced water usage it is essential that little used outlets – hot and cold – have a weekly flushing regime.
  • To check that increased flushing has been effective, you may want to consider extra microbiological sampling.

Cold Water Storage Tanks:

  • HSG 274 guidance states that tanks should be turned over (water within them used up) every 24 hours to prevent stagnation from occurring.
  • Any site with a tank should increase flushing of tank fed outlets. This should happen at least weekly to help keep the system water moving.
  • If possible, the tank capacity, or number of tanks in use should also be reduced.

Water Heaters:

  • If hot water is not required the water heater can be turned off without causing water hygiene issues; as long as the water is stored at less than 20˚C (like cold water). It can then be managed in a similar way to a cold water tank, with outlets flushed daily or as frequently as possible.

Cooling Towers:

  • Cooling tower system/s that are not required during the closure period can be shut down. We  would only recommend this, however, in the case of a full lockdown; i.e. where it would be impossible to access site to carry out maintenance (and valves are known to hold).
  • Daily and weekly testing and associated tasks must be maintained. Dipslides, TVC and Legionella sampling should continue at the usual frequencies.

Water Softener:

  • The salt level in the brine tank should be checked regularly and topped up if required. It is likely that the amount of softened water required will be less than usual.

Closed systems:

  • BMS/manual valve exercising should be continued as normal to ensure circulation is           occurring.
  • If you have a remote monitoring system installed (e.g. Hevasure) it is important that you continue to check this and regularly communicate with your specialist/account manager to ensure the systems are being maintained well.
  • Remote monitoring is an ideal solution for minimising people on site and safely checking the condition of closed water system. If mothballing is the only option, the new SF30 guidance, which details specific frequencies and protocols per building asset, should be referred to.

How can Guardian Water Treatment help?

Ongoing water treatment regime: As an essential service, our water treatment engineers are still helping to keep our clients’ sites free from legionella and corrosion. All of our staff are fully briefed on safe working practices to prevent the spread of COVID 19. In most cases, these works are solitary with minimal risk of contact with other people – particularly in buildings that are currently empty.

We can help advise on adjusting your water treatment regimes in order to ensure that when normal service resumes, your building is safe and ready to hit the ground running, with no nasty legionella or corrosion issues lurking in your tanks and pipework.

Download our guide to legionella treatment in low occupancy buildings, here.

Free webinars: We are hosting a series of webinars, designed to brief FMs and maintenance teams on how to keep their buildings’ water treatment systems clean and ready for action during this period of lockdown.

You can find out more and sign up to attend the next webinar, by emailing Sam Harris, samanthah@gwtltd.com.

Guardian Water Treatment is a member of the Legionella Control Association, click here for more information.