Key points
- An espresso machine with a steam boiler is a pressure system under the Pressure Systems Safety Regulations 2000 (PSSR).
- The 250 bar litre exemption in PSSR does not apply to steam. Small boiler size does not take an espresso machine out of scope.
- Before the machine is used, there must be a written scheme of examination drawn up or certified by a competent person.
- The competent person sets the examination interval in the scheme. Local authority guidance for coffee machines often cites at least every 14 months.
- Examination is not maintenance. Safety valves, water treatment, gaskets and descaling still need a planned schedule.
Why espresso machines are pressure systems
A traditional espresso machine heats water in a sealed boiler to make steam for milk and hot water for tea and Americanos. The steam boiler typically runs at around 1 to 1.5 bar. It sits on the counter at the busiest point in the room, a short distance from staff and customers.
PSSR 2000 applies to a pressure system: one or more rigid pressure vessels, with associated pipework and protective devices, that contain or are liable to contain a relevant fluid. Regulation 2 defines a relevant fluid as:
- steam; or
- any gas, or liquid whose vapour pressure is above atmospheric, at a pressure greater than 0.5 bar above atmospheric pressure.
Steam is listed on its own. So a sealed boiler that produces steam is within the definition, and an espresso machine's steam boiler, its pipework and its safety devices make up a pressure system.
The 250 bar litre rule, and why it does not help
PSSR has an exemption for small systems. Schedule 1, Part II says that the key duties, including the written scheme and examination (regulations 5(4), 8 to 10 and 14), do not apply to a pressure system containing a relevant fluid other than steam where the pressure multiplied by the internal volume of the largest vessel is less than 250 bar litres.
An espresso machine boiler of 10 litres at 1.5 bar is about 15 bar litres, far below that threshold. That is why some people assume coffee machines are exempt. They are not, because the exemption excludes steam.
"It's under 250 bar litres, so it doesn't need a scheme" is wrong for any machine with a steam boiler. The exemption only applies to systems containing a relevant fluid other than steam.
Machines without a pressurised steam boiler, such as some filter brewers and open-vented water boilers, may not be pressure systems at all. Bean-to-cup machines vary by design. If you are not sure whether a machine is in scope, ask a competent person to assess it and record the answer.
The written scheme of examination
Regulation 8 says the user of an installed system (or the owner of a mobile one) must not operate it, or allow it to be operated, unless there is a written scheme for its periodic examination. The scheme must be drawn up, or certified as suitable, by a competent person.
A plumbed-in espresso machine is normally treated as an installed system. In practice that puts the duty on the business that operates it, even if the machine is leased or loaned by a coffee supplier.
A written scheme for an espresso machine will usually cover:
- Which parts are included: the steam boiler, any separate pressurised water or brew boilers, connecting pipework and protective devices.
- The protective devices: safety (pressure relief) valve, pressure gauge, pressurestat, boiler water level control and heating element cut-out.
- The nature of the examination, such as external visual checks and any internal inspection where practicable.
- Any preparation needed, such as isolating and cooling the machine.
- The maximum interval between examinations.
- Any special measures needed before the system is first used, or after repair or modification.
The scheme should be reviewed when the machine is modified, moved to a very different use or repaired in a way that affects its pressure parts.
The competent person and examination intervals
PSSR defines a competent person as a competent individual (other than an employee of the user) or a competent body. HSE guidance stresses three things: the necessary knowledge, practical experience and enough independence to make impartial judgements.
For coffee machines, the competent person is usually one of:
- The engineering inspection service attached to your insurer, or an independent inspection body.
- A coffee machine service company that has the competence and independence to draw up schemes and carry out examinations.
The legal interval is whatever the written scheme says. There is no single number in the regulations. Local authority guidance on coffee machines, including notes published by several councils, commonly cites examination at least every 14 months, which matches a typical annual cycle with tolerance. Busy machines or those with a poor history may be given shorter intervals.
| Item | Who decides | What to keep |
|---|---|---|
| Whether the machine is in scope | Competent person, on your behalf | A note on the asset record |
| Written scheme of examination | Competent person draws up or certifies it | The scheme document, per machine |
| Examination interval | Set in the scheme | Next due date on the asset |
| Examination report | Competent person | Every report, including any defects and deadlines |
| Safe operating limits | User, with manufacturer information | Boiler pressure range and safety valve setting |
If the examination finds a defect that gives rise to imminent danger, regulation 10 requires the competent person to give the user a written report straight away, and the machine must not be used until the defect is fixed. The competent person must also send a written report to the enforcing authority within 14 days.
Many engineering and combined commercial insurance policies require pressure equipment to be inspected, and some insurers provide the inspection. A lapsed examination can affect cover as well as compliance. Check your policy wording, and match the inspector's schedule to your scheme.
Routine maintenance that keeps the boiler safe
PSSR also requires the system to be properly maintained (regulation 12) and operated within its safe operating limits (regulation 7). A clean certificate on the wall does not make up for poor day-to-day care. These are the maintenance tasks that matter most for safety and reliability.
Safety valve
The safety valve is the last line of defence if the pressurestat fails. Scale and milk residue can cause it to stick. It should be checked at each service and examination, and replaced on the interval the manufacturer or competent person recommends. Never adjust, plug or remove a safety valve, and never fit one with a different setting.
Water treatment and filtration
Limescale is the root cause of many espresso machine failures. It coats heating elements, blocks level probes and can stop valves working. The best defence is prevention: a filtration or softening system sized to your local water hardness and your volume, with cartridges changed by litres treated rather than by guesswork. Test water hardness at each site, because it can vary a lot across the UK.
Descaling
Where scale has built up, descaling should be done by a trained engineer following the manufacturer's procedure. Some manufacturers advise against routine chemical descaling of the boiler on site. Poorly done descaling can damage seals and leave chemical residue, so check the machine maker's guidance and treat repeated scaling as a water treatment problem.
Group heads, gaskets and screens
Group head gaskets and shower screens wear with use and heat. On busy sites they are often replaced every few months. Worn gaskets leak hot water and pressure at the group, which is a scald risk for baristas. Daily backflushing and cleaning, as the manufacturer describes, extends their life.
Steam wands and other checks
Check steam wands, valves and vacuum breakers for leaks and blockages, and look at hoses, electrical connections and the drain. Train staff to purge steam wands and to report hissing, unusual pressure readings or water from the safety valve.
A sample espresso machine maintenance schedule
| Task | Typical frequency | Who |
|---|---|---|
| Backflush groups, clean baskets, purge and wipe steam wands | Daily (per manufacturer) | Baristas |
| Check boiler pressure gauge is in normal range | Daily | Baristas |
| Soak portafilters and clean group screens | Weekly or more often | Baristas |
| Replace water filter cartridge | By litres treated and water hardness | Engineer |
| Replace group gaskets and shower screens | By usage; often every few months on busy sites | Engineer |
| Preventative service, including safety valve and protective device checks | Per manufacturer and usage, often 6 or 12 monthly | Engineer |
| Examination under the written scheme | As stated in the scheme | Competent person |
Managing machines across many sites
For a café group or caterer with dozens of machines, the risk is not one big failure of process. It is quiet gaps: a machine moved between sites without its scheme, a leased machine nobody thought was the operator's responsibility, or a defect noted on a report and never fixed.
- Give every machine a unique asset ID and record its serial number and location.
- Store each machine's written scheme and examination reports against the asset, not the site.
- Track the next examination date alongside service and filter change dates.
- Agree in writing who arranges the examination for leased or loaned machines.
- Raise any defects from an examination as jobs with deadlines.
Fabric FM was built by a team that services coffee machines for cafés, caterers and workplaces, so these records are a first-class part of the platform. Schemes, examinations and service visits sit on each machine's record across every site. See compliance management software for more, now in early access.
This guide is general information, not legal advice. Check the current regulations and guidance, or speak to a competent person, for your premises.
