With a further delay of 4 weeks until we can think about starting to return to a more normal way of life for many people this means the buildings where they work will be largely empty once again.

If buildings have been closed or part occupied during the pandemic stagnation of the water system can happen, especially where no additional control measures have been put into place. When this occurs legionella bacteria can grow, increasing the risk of Legionnaires’ disease, which affects people in a very similar way to Coronavirus.

Reviewing the risk assessment and managing the legionella risks are important when you reinstate a water system or restart some types of air conditioning units.

Small wall or ceiling-mounted units with closed cooling systems should not present a risk. Larger units may present a risk if they have improperly drained condensate trays, or humidifier or evaporative cooling sections where water can stagnate, becoming a reservoir for bacteria to grow.

When you review your risk assessment, decide what the risks are for your units and if you need to clean them safely, before they are turned on.