Coronavirus, vacant buildings and Legionella risks

With the current Government Coronavirus advice and requirements for ‘lockdown’, many buildings will be empty or experiencing minimal occupancy as a result. Did you know that in such situations the domestic water systems within your building(s) could potentially become a legionella risk?

Low or zero water use allows water to stagnate, providing conditions where harmful legionella bacteria can proliferate. Therefore Ingleton Wood recommend that clients are aware of their legal obligations and review the changing legionella risks in these unprecedented times. These are essential to prevent or control the risk of exposure to legionella, in order to protect occupants and visitors.

The HSE (Health and Safety Executive) have specific guidance for operating and maintaining domestic water systems in order to meet legislation, which can be found under the resources section here:

https://www.hse.gov.uk/legionnaires/

Building owners, managers and landlords have legal obligations under the above HSE directives. Whilst buildings are closed or under reduced occupancy, consideration should be given to identifying the potentially different and challenging legionella risks posed by these uncertain times. It is recommended that the above document is reviewed in full, however in summary, the responsible person should be aware of the need to:

Review the legionella risk assessment and written control scheme, particularly with current occupancy and operations in mind
Identify low use water outlets and set up a flushing regime
Identify if occupants or visitors may be more susceptible to legionella and control the risk
Ensure flushing of low or zero use outlets on a regular basis and recording of such activities
Ensure routine water temperature testing records are maintained
Ensure that water systems which have been left stagnant are recommissioned as if new (i.e. sterilising, microbiological testing)

It is not necessarily recommended to drain down mothballed systems as this does not always eliminate the legionella risk.

One of the greatest risks for potential exposure to legionella for vacant buildings will be upon reoccupation, and it is therefore essential that the water systems are made safe prior to occupation.

In all circumstances the flushing of water should be exercised with caution as there is potential for stagnant water to form aerosols which may contain legionella bacteria. The client’s risk assessment should identify the risks and control measures required. If there is any doubt, a specialist water treatment company should be engaged to assist prior to the building being reoccupied.

We hope the above information is useful in aiding getting your building(s) back into safe and full operation. Stay safe!