Following the announcement by Boris Johnson earlier this week, we are aware that many of our clients will have taken the difficult decisions to reduce staffing levels or the closure of their buildings, to assist in reducing the spread of Covid-19.
However, please be aware that such actions can increase the chances of Legionella surviving in water systems as a direct result of low turnover of water within systems that are not being used as frequently, or as a result of existing control measures that are in place not being implemented at times of closure or low occupancy.
We have received guidance from the Legionella Control Association (LCA) regarding what the expectation is for the management of water systems during this period of COVID-19 precautions.
“The Health and Safety at Work Act still applies and Duty Holders must still take reasonable practical steps to control the risk from Legionella throughout this period of time. Duty Holders implicated in an outbreak of Legionnaires disease, resulting from actions taken for COVID-19 precautions are not likely to have any exemption from prosecution.”
Each Duty Holder must make their own determination for each circumstance, but the following principles should be considered when making decisions on what to do to control Legionella during the COVID-19 outbreak.
Closing down or mothballing buildings?
Should the difficult decision be made to shut down or mothball buildings, due to a reduction in workforce or the temporarily shutdown of the business during the COVID-19 outbreak, we advise the following control measures are implemented:
- Where possible, it is advised that all stored water is drained down to reduce the potential of stagnation of water within water systems.
- If this cannot be carried out, then it is recommended to reduce the volume of stored water to ensure that there is a maximum of 24 hours’ worth of stored water.
- Revise your sites current infrequently used outlet list and amend to include outlets in areas that have been mothballed.
- Increase the flushing of infrequency used outlets, recording this action in the log book.
- Ensure all cold water is stored and delivered from outlets at less than 20°C.
- Ensure all stored hot water above a capacity of 15 litres is stored at a minimum temperature of 60°C.
- Ensure all stored hot water below a capacity of 15 litres is stored between 50°C - 60°C.
- Any hose pipes, water systems and appliances/machinery without back flow protection as per water regulations, should be disconnected when not in use.
Recommissioning of water systems
When the spread of COVID-19 can be controlled and normal life as we know it can be resumed, and businesses start to re-open. It is essential that water systems are not simply put back in to use. It is sensible to put together a recommissioning plan for each water system within the building, to provide reassurance to people returning to work that the water systems are safe for normal use. To ensure the safety of employees throughout the business, the following control measures are recommended:
- A chemical disinfection of all Cold water storage tanks, storage vessels & header tanks, where possible including their associated water systems.
- A thermal disinfection/ pasteurisation or all hot water heaters, where possible including their associated water systems.
- Ensure all outlets and associated systems are flushed thoroughly.
- Expansion vessel are purged and drained.
- Where possible samples of the water should be taken ensure all control measures implemented were successful in reducing the proliferation of bacteria.
- Shower heads, hoses & spray heads should be dismantled, cleaned and chlorinated.
- Limescale should be removed from outlets.
- Check water softening equipment is fit for use.
There is potential for multiple outbreaks of Legionnaires’ disease following the COVID-19 outbreak if actions taken now are not carefully considered and additional controls put in place for when normal life returns. Please be aware that the responsibility for Legionella control lies with the Duty Holder. Bradley Environmental are here to assist you in ensuring that you consider any risks presented from your water systems as a result of actions taken in your efforts to control the COVID-19 outbreak.
