What is legionella control?
Legionella control is managing water systems to prevent the growth and spread of legionella bacteria, through a risk assessment, a written scheme of control and recorded monitoring.
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<a href="https://facilityoptix.co.uk/glossary/legionella">What is legionella control?</a> — diagram by
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</figure>Temperature and stagnation are the two conditions the whole regime is arranged against — water held where bacteria grow, and water that sits still long enough for them to.
Little-used outlets are the recurring failure. Flushing them is trivial work, easy to skip, and impossible to evidence afterwards if it was not recorded at the time.
The roles are defined: a duty holder, a responsible person appointed and trained, and competent people carrying out the monitoring. Appointing in name without the training is a common gap.
In practice
A monitoring log full of ticks.
Temperatures are recorded as satisfactory. There are no numbers anywhere, so a system drifting slowly out of range looks identical to one holding steady.
Readings are the data and a tick is a conclusion, and only one of them can be re-read later to show a trend.
The log that proves compliance and shows nothing is the commonest form of this record.
What goes wrong in practice
- Flushing records kept on paper at the outlet and never collated.
- Out-of-range temperatures recorded and not actioned.
- Risk assessment not reviewed after changes to the system or the building's occupancy.