Showers create a fine spray at face height, which is exactly how legionella reaches the lungs. Scale and slime inside the shower head and hose give the bacteria somewhere to grow. Cleaning and descaling them regularly is one of the simplest legionella controls there is.
Why shower heads are a risk
- Water left in the head and hose after use sits at room temperature.
- Limescale gives bacteria a surface to cling to and shelters them from heat and disinfectant.
- Flexible hoses can trap water and support slime on the inside.
- A shower that is rarely used holds that water for days or weeks.
How to clean and descale a shower head
- Remove the head and hose from the fitting.
- Dismantle the head as far as the design allows and brush away loose scale and debris.
- Descale by soaking the parts in a descaling solution, following the product instructions.
- Rinse thoroughly with clean water.
- Disinfect by soaking in a suitable disinfectant for the contact time on the label.
- Rinse again, reassemble and refit.
- Run the shower for a couple of minutes, keeping spray to a minimum, before it goes back into use.
- Record the date, the location and who did it.
Wear gloves and eye protection, and never mix cleaning chemicals. Replace heads and hoses that are heavily scaled, cracked or damaged.
How often
Your legionella risk assessment sets the frequency. Quarterly is a common starting point, with more frequent cleaning in hard water areas, in healthcare settings and wherever scale builds up quickly.
Showers that are not used often
Cleaning is not enough if water stands in the pipe behind the shower. Run little-used showers on a set schedule, typically weekly, for long enough to bring fresh water through. Point the head down into the tray or cover it to limit spray while you flush.
Where this matters most
- Nursing homes and care settings, where residents are more vulnerable.
- Hotels and B&Bs with rooms that sit empty.
- Gyms, sports clubs and schools with rows of showers.
- Workplaces with staff showers that few people use.
Do not forget the rest of the system
A clean shower head on a system with lukewarm hot water will be recolonised. Temperature control comes first. See our guide to water temperatures for legionella control.
Safer Solutions provides shower head cleaning and disinfection, legionella risk assessments and sampling across Ireland. Call 086 275 9728, email info@safersolutions.ie or request a quote.