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Covid about Legionella?

Indoor gyms and swimming pools are already open in Northern Ireland and England, opened today in Wales and are set to open on 14th September in Scotland - although the Scottish September date may be brought forward when reviewed on 20th August.

What's the guidance?

Changing and showering facilities associated with (open) sport and leisure clubs remain closed in Northern Ireland - until further guidance is issued1. Current advice from UK Government2, Swim England3 and UKActive4 is to arrive at the facility dressed and ready to play or swim, then travel home afterwards to change and shower.  The objective is to minimise time spent in the changing room and avoid the shower facilities to help maintain the (pool?) water quality3

Use of changing rooms and showering facilities should in general be avoided where possible, although these must be available for participants with disabilities or special needs and are likely to be needed after swimming2.  

Swim Wales’ Return to Water Participant Guidance5 states: showers may be available at the pool, and on leaving the pool, it’s recommended to shower again before leaving the facility.  No specific guidance is yet available for Scotland.

Is the guidance good?

So, fully closed shower facilities in Northern Ireland, and operational, at least for a post-swim shower, at pools. Assuming the correct measures were put in place before and during the shutdown, and ahead of reopening, this is a perfectly good status. 

In England, however, shower facilities in gyms and other sports venues are open but visitors are discouraged from using them, likely due to possible difficulties around social distancing. Seldom used showers, however, can cause a water quality problem of a different kind...

Unintended consequences

Let's think about water distribution around the building, serving wash-hand basins, toilets and showers. Infrequent use, of the showers especially, is a problem - water lying in the pipework supply will cool to the ambient temperature, and stagnate between users. At next actuation, the cooled water will be purged to drain - as warm water is drawn through to the shower head - the point from which the next showering event usually commences.  This is not good for any shower system, which has been sized for an expected flow demand and turnover of water.  It’s wasteful of pre-heated water and creates stagnant deadlegs to lesser used shower heads (especially in group shower arrangements), compromising water quality through the proliferation of Legionella bacteria and biofilm formation.

Legionella is widely known to cause Legionnaires Disease, a type of pneumonia and infection that is acquired when contaminated aerosols are inhaled, often via shower heads of poorly used and maintained water systems… …contaminated aerosols, pneumonia… something sounds familiar!

L8 Duty of Care

Facility operators therefore need to be mindful not to fall foul of L8 Legionella control guidelines as they make their premises Covid-safe. It may take some careful and creative thinking to accommodate social distancing whilst maximising the use of showers and improving water turnover.

We'd advise, as a general rule, to practice regular high velocity flushing - to flush biofilm growth away to drain and improve water quality.

If turnover, however, remains low, a duty flush of all shower heads can keeps things ticking along.



  1. Guidance on the safe phased return of sport, leisure and recreation in Northern Ireland. July 2020. Department for Communities.
  2. Providers of grassroots sports and gym/leisure facilities – Working safely during coronavirus (COVID-19) – Guidance – GOV.UK
  3. Returning to the Pool; Guidance for Users, version 6, 23 July 2020. Swim England.
  4. Covid-19- A framework for the re-opening of gym, leisure centre and wider fitness industry during social distancing. Version 2, 14 July 2020. UK Active.
  5. Return to Water, guidance for participants. July 2020. Swim Wales.