Legionella Control in a Care Home
A 42-bed care home has two wings. The hot water calorifier is set to 55°C and the return temperature is 48°C. A sentinel shower on the second floor runs at 46°C after one minute. The east wing shower room has been closed for six months but remains connected; there are two dead legs from a 2016 extension. The water safety file contains a schematic dated 2014 but no current risk assessment. A contractor flushes outlets monthly, but records show only ticks, no temperatures. A sample from the closed shower room returns 1,200 cfu/l Legionella. Three residents are on immunosuppressant therapy, and one has a urinary catheter. The registered manager says the home is 'low risk because it is a domestic setting' and asks whether the sample result can be ignored until the next inspection.
1. Evaluate the care home's legionella management and explain why the manager's 'domestic setting' argument is unsafe.
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The manager's argument is wrong. A care home is a workplace and a residential setting with a vulnerable population; the water system is not a domestic system in the sense that it can be left unmanaged. The risk assessment is absent, the schematic is nine years out of date and the contractor's records contain ticks but no temperatures. Those are signs of a system that is not being controlled.
The temperatures support that view. Hot water should be stored at 60°C and distributed at 55°C, with sentinel outlets reaching at least 50°C within one minute; the calorifier at 55°C, return at 48°C and shower at 46°C are below the expected control range. The closed shower room and two dead legs create stagnation, biofilm and a place for Legionella to multiply. A result of 1,200 cfu/l is above the action level; it requires immediate review and remedial action, not waiting for an inspection.
The three immunosuppressed residents and the resident with a catheter are at increased risk of infection. The absence of a current risk assessment means the home cannot show that it has identified the risk, implemented controls or monitored them. The 'low risk' label is therefore not evidence-based.
2. Recommend immediate and short-term actions, including how to protect residents while remedial work is done.
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Immediately take the affected shower room out of service and label it; do not use it for washing or cleaning. Inform the registered manager and the person responsible for water safety. Arrange a competent water safety assessment of the whole system, not just the sampled outlet, and update the schematic.
Short term: adjust the calorifier to achieve 60°C storage and 55°C distribution, with TMVs at outlets to prevent scalding of residents. Clean and chlorinate (or thermally treat) the affected outlet and little-used sections; flush all dead legs and remove them where practicable. Increase temperature monitoring at sentinels, record results and act on out-of-range values. Retest after remediation.
Protect residents by using alternative washing facilities, checking that water is not too hot at the point of use, and telling staff what to do if a resident develops respiratory symptoms. If a case of Legionnaires' disease is suspected, seek urgent public health advice. Do not rely on the contractor's tick sheet: require dated temperature records, signed corrective actions and a named responsible person. The reasoning is that the sample result is a system warning, not an isolated outlet problem.
3. Explain how the home should govern the contractor and its records so that the control scheme is sustainable.
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Start with a written contract that defines competence, scope, method, frequency, reporting and escalation. The contractor should not simply 'flush and tick'; it should measure and record sentinel temperatures, return temperatures, any remedial work and the reason for any deviation. The home should check the contractor's competence and insurance, and review the method statement before work.
Appoint a named responsible person and a deputy, with a water safety group or equivalent. Keep a live schematic, risk assessment, logbook, sampling results and training records. Use a permit or change-control process for new building work, because the 2016 extension created the dead legs. Review the risk assessment annually or when the system, occupancy or use changes. Audit a sample of records quarterly and follow up missing data.
The reasoning is that Legionella control depends on routine verification, not a one-off clean. The home must be able to show who did what, when, with what result and what happened next. If the contractor cannot provide that, the home remains accountable and should change the arrangement.