Many offices are busy two or three days a week and quiet the rest. Fewer people means fewer flushes, fewer showers and less water running through pipes. That can leave water standing in exactly the conditions legionella bacteria like.
Where quiet offices can go wrong
- Washrooms and kitchenettes used much less than the system was designed for.
- Showers for cyclists and runners that are rarely used.
- Whole floors or wings closed or rarely occupied.
- Hot water systems set up for a bigger workforce.
- Cold water tanks holding more water than the building now uses.
Practical steps
- Review your risk assessment when occupancy changes. A plan for a full building may not suit a half-empty one.
- Flush little-used outlets regularly and record it. See dead legs and little-used outlets.
- Check temperatures in hot and cold systems.
- Consider reducing unused plant and storage with your advisers, so water does not sit for long.
- Keep a logbook and name who is responsible. See who is responsible for legionella control.
- Plan for reopening areas. Our reopening checklist helps.
Your duties
Employers and those in control of premises must manage risks to health under the Safety, Health and Welfare at Work Act 2005. The HPSC national guidelines give practical advice on legionella control.
What changes when an office is half empty
Hybrid working has left many offices with a lot of capacity and fewer people. Taps, showers, kitchenettes and toilets that were once used daily may now be used a couple of times a week, or not at all. That is the situation in which stagnant water, warm spots and biofilm build up. Our guide to biofilm explains why that matters.
Practical questions to ask about your building
- Which outlets are rarely used? Think of washrooms on quiet floors, showers, kitchen taps and any outlet at the end of a long pipe run.
- Is anything now unused? Floors that are closed, stores, old kitchens and capped pipework (dead legs) can hold water that never moves.
- Has occupancy or layout changed since your last risk assessment? A change in how a building is used is a typical reason to review the assessment.
- Who is flushing, and is it recorded? Regular flushing of little-used outlets is a common control measure. It only works if it is done, by someone who knows the plan, and written down.
- What happens on holiday weeks and shutdowns? Our reopening checklist sets out sensible steps after a quiet spell.
Simple controls that usually help
- Draw up a list of every outlet and mark how often each is used.
- Set a flushing routine for outlets that are used less than weekly, and assign it to a named person.
- Remove or isolate unused pipework and outlets where it is safe to do so.
- Keep hot water hot and cold water cold, and check them on a schedule.
- Keep a logbook of flushing, temperature checks and any works.
- Ask your risk assessor to review the system if the building is now used very differently.
Where sampling fits
For buildings that have seen big changes in use, a risk assessment tells you what could go wrong and sampling can check what the water is actually doing. Our article on Legionella sampling versus risk assessment explains how the two work together, and how often sampling is typically done.
We work with offices in Dublin, Cork, Limerick and Galway. See our Dublin page for more.
Talk to Safer Solutions
A refreshed legionella risk assessment shows what has changed and what to do. Call 086 275 9728 or email info@safersolutions.ie for a friendly chat.
If your building has storage tanks, Safer Solutions also offers water tank cleaning and disinfection. Email info@safersolutions.ie to talk it through.