Key points
- Legionella control is a legal duty under the Health and Safety at Work etc Act 1974 and COSHH 2002. HSE's ACOP L8 and technical guidance HSG274 Part 2 explain how to meet it.
- You need a risk assessment, a written control scheme where risks are identified, and a named responsible person to manage it.
- Key temperatures: stored hot water at 60°C or above, hot water reaching 50°C at outlets within one minute, cold water below 20°C within two minutes.
- Flush little-used outlets at least weekly and record monthly temperature checks at sentinel outlets.
- Keep records for at least five years.
Why legionella applies to restaurants
Legionella bacteria are common in natural water. They grow in water between about 20°C and 45°C, especially where water sits still and where there is scale, sludge or biofilm. People become infected by breathing in small droplets of contaminated water, for example from a tap, a spray head or a shower.
A restaurant or café has the ingredients for risk: hot water cylinders or water heaters, long pipe runs to hand basins, pre-rinse spray arms in the wash-up, staff showers, and outlets that are rarely used. Ice machines, coffee machines and drinks dispensers are fed from the cold supply too.
The duty to manage the risk falls on employers and on anyone in control of premises. In a leased unit, the tenant usually controls the water system inside the unit, while the landlord may control shared tanks or plant. Agree who does what in writing.
The law and the guidance
Three pieces of law create the duty:
- The Health and Safety at Work etc Act 1974, which requires risks to employees and others to be controlled.
- The Management of Health and Safety at Work Regulations 1999, which require risk assessment.
- The Control of Substances Hazardous to Health Regulations 2002 (COSHH), which cover biological agents including legionella.
HSE's Approved Code of Practice, L8, explains how to comply. It has special legal status: if you do not follow it, you would need to show you have complied in some other way that is at least as good. HSG274 Part 2 gives the technical detail for hot and cold water systems, including the temperatures and check frequencies below.
The risk assessment
The risk assessment identifies where legionella could grow and spread in your water system, who could be exposed, and how the risk is controlled. For a small café with a combi heater and a few outlets it may be short. For a large restaurant with stored hot water, tanks and showers it will be more detailed.
What it should cover
- A description of the water system, ideally with a simple schematic.
- Sources of risk: stored water, dead legs, little-used outlets, spray-producing equipment, temperatures in the growth range.
- People at risk, such as staff, customers, and anyone more vulnerable.
- The control measures in place and how they are checked.
- The name of the responsible person.
Who can do it
The assessment must be done by a competent person. HSE says many simple systems can be assessed by the duty holder or a member of staff with suitable knowledge. Larger or more complex systems usually need a specialist water hygiene consultant. If you use a contractor, you are still responsible for acting on what they find.
When to review it
HSE guidance does not set a fixed review date. Review it regularly, and whenever there is reason to suspect it is no longer valid. Triggers include changes to the water system or its use, a refit, a change in the people at risk, monitoring that shows control is failing, or a case of Legionnaires' disease linked to the site. Many operators set a routine review date as a backstop, but the right interval is a matter of judgement.
ACOP L8 expects the duty holder to appoint a competent person, often called the responsible person, to manage legionella control day to day. In a single site this is often the general manager. Across several sites, make sure each site has a named person and a deputy.
Temperature control and monitoring
Temperature is the most common control in hot and cold water systems. The aim is to keep hot water above, and cold water below, the range where legionella grows.
| Check | Target | Typical frequency (HSG274 Part 2) |
|---|---|---|
| Stored hot water (cylinder or calorifier flow) | 60°C or above | Monthly |
| Hot water return to cylinder, where there is a circulating system | 50°C or above | Monthly |
| Hot water at sentinel outlets (nearest and furthest from the heater) | At least 50°C within one minute of running | Monthly |
| Cold water at sentinel outlets | Below 20°C within two minutes of running | Monthly |
| Cold water storage tank, if fitted | Below 20°C; tank condition inspected | Temperature every six months; condition annually |
| Little-used outlets | Flushed until water reaches normal temperature | At least weekly |
| Showerheads and hoses | Cleaned and descaled | Quarterly, or as the risk assessment requires |
Sentinel outlets are the taps nearest and furthest from the water heater or tank. If they are in range, the rest of the system usually is too. HSG274 also recommends checking a representative sample of other outlets on a rotating basis.
Water at 50°C or above can scald. Where vulnerable people could use an outlet, thermostatic mixing valves may be fitted. These need their own maintenance, and the pipe on the outlet side of the valve is a place where legionella can grow, so keep that pipe short.
Flushing little-used outlets
Stagnant water is one of the biggest risks in a restaurant. A hand basin in a storeroom, a spare toilet, an unused shower or a tap in a closed function room can all sit for days.
- Flush little-used outlets at least weekly, until the water reaches its normal temperature.
- Run water gently to avoid creating spray, and take care with showers.
- Record each flush, with the date, outlet and who did it.
- If an outlet is not needed, ask a plumber to remove it and cut back the pipe to avoid leaving a dead leg.
If a site has been shut for a period, such as a seasonal closure or a refit, flush the whole system before reopening and check temperatures. Your risk assessment should say what to do.
Kitchen equipment to include
Water-using equipment should be part of the assessment. Common items in restaurants and cafés are:
- Pre-rinse spray arms at the pot wash, which create aerosol.
- Ice machines, which need regular cleaning and filter changes.
- Coffee machines and water filters, which are fed by the cold supply and should be maintained to the manufacturer's schedule.
- Staff showers and any customer showers in gyms or hotels.
- Drinks dispensers and soft drink lines.
Record keeping
HSE guidance says you should keep records of the risk assessment, the control scheme, the people responsible, and the results of monitoring, inspection and checks, for at least five years. Records should also show any remedial work, such as a heater adjusted after a low reading.
A clipboard in the back office is fine until there are several sites or a staff change. The common failure is that checks happen but the records cannot be found, or out-of-range readings are written down without anyone acting on them. The wider set of kitchen checks is in our commercial kitchen compliance checklist, and our PPM schedule template shows how to plan routine tasks across sites.
Fabric FM can schedule weekly flushing and monthly temperature checks for each site, keep the risk assessment and its review date against the building, and raise a job when a reading is out of range. It is in early access; see our compliance management software page.
This guide is general information, not legal advice. Check the current regulations and guidance, or speak to a competent person, for your premises.
