The Government during the current period have not stated any special measures to exempt responsible person/s from the ‘Health and Safety at Work Act 1974’, under which statutory requirements of ACOP L8 (The Legionnaires’ disease Approved Code of Practice) & HSG274 (Legionnaires’ disease Technical guidance) guidance fall.
The Legionella Control Association (LCA) advises,
“Although controls in place may need to be adapted to changing circumstances, duty holders must still be able to demonstrate control of risk to a reasonably practicable level.”
If a building is closed or minimal access is required, water systems usage will be much lower than usual due to the reduced footfall in normal operating conditions. You will also need to consider the reduced capacity from onsite maintenance teams, which will be to a minimum over the coming weeks.
Record all information in the site logbook.
As a guide the water should be flushed until the water reaches within 2 degrees of the temperature of the incoming mains water.
Generally minimum of 2 minutes per outlet to be sufficient in most cases.
Extra microbiological sampling may be considered to check how effective the flushing has been with reduced water usage.
Cold Water Storage Tanks
If possible try to reduce the amount of water stored onsite by reducing the number of tanks in use. All tanks should be turned over every 24 hours to prevent stagnation occurring and to keep inline with HSG 274 guidelines. Any site with a tank should incorporate daily flushing of tank fed outlets. If this is not possible, doing this weekly will keep the system water moving.
If a tank is isolated for a period of time it should be drained or left full (and clearly labelled) and chlorinated before it is reinstated.
As long as the water is stored at less than 20˚C with no water hygiene issues, turning off the water heater is the simplest option if hot water is not required in the building. It can then be managed in a similar way to a cold water tank as above. Before the building returns to normal use and the unit is reinstated, it is recommended pasteurisation is carried out.
In the event of a full lockdown it isrecommend shutting down the cooling tower system/s if it is not needed. It is essential that if this is carried out the towers will need to be cleaned and disinfected prior to being returned to service. As always, it is important that you continue to maintain your daily and weekly testing/ tasks during this time. Dipslides, TVC and Legionella sampling should continue at the usual frequencies.
It is likely that the amount of softened water required will be less than usual, however the salt level in the brine tank should be checked regularly and topped up if required.
BMS/manual valve exercising for these systems should continue as normal to ensure circulation is occurring.