TR19 Kitchen Extract Cleaning Requirements: 2026 Guide
Last updated: 10 October 2026
TR19 kitchen extract cleaning requirements set the cleaning frequency, grease-deposit limits and certification standard for commercial kitchen ventilation in the UK, published by the Building Engineering Services Association (BESA). Heavy-use kitchens need cleaning every three months, and grease deposits must not exceed a mean average of 200 microns between scheduled cleans, according to BESA.
Key Takeaways
- Priority First notes that TR19 is published by BESA, the Building Engineering Services Association, and sets the UK benchmark for kitchen extract hygiene and ventilation cleanliness.
- Grease deposits must stay below a mean average of 200 microns between scheduled cleans under TR19 Grease, with 500 microns or more triggering immediate spot cleaning, according to BESA.
- Around 70% of commercial kitchen fires start in extract ventilation systems due to fat and grease build-up, according to Kent Fire and Rescue Service.
- Heavy-use kitchens require cleaning every three months, moderate-use kitchens every six months and light-use kitchens every twelve months, according to BESA.
- A TR19-compliant system can cut High Risk Combustion Load Levels by 83% once brought into compliance, according to Wikipedia, citing BESA TR19 guidelines.
What is TR19 and which organisation publishes it?
TR19 is a technical specification for the internal cleanliness of ventilation systems, published by the Building Engineering Services Association (BESA) — the UK trade body representing building services contractors. BESA introduced the original TR19 guidelines in 2005 by merging two earlier documents, TR/17 and DW/TM2, into a single standard, according to Wikipedia.
The specification was updated in 2014 to align with BS EN 15780:2011, the European standard for ventilation ductwork cleanliness. BESA then revised the full guide again in July 2019, and in 2020 it split the kitchen extract section out into a stand-alone document called TR19 Grease, according to the NBS Publication Index.
TR19 Grease now sits alongside TR19 Air, the general ventilation ductwork cleanliness specification, as the two working documents facilities managers reference. For facilities managers overseeing prime commercial and residential buildings, understanding which document applies — and when — is the starting point for any facilities management compliance programme.
Legal obligations for UK businesses under TR19 and fire safety law
TR19 itself is not a law — it is an industry specification — but UK businesses have a direct legal duty to keep kitchen extract systems safe under the Regulatory Reform (Fire Safety) Order 2005. The Order places that duty on the "responsible person", typically the employer or building occupier, who must carry out and maintain a fire risk assessment covering kitchen ventilation.
Fire and rescue authorities across England and Wales treat TR19 compliance as the recognised benchmark for discharging that duty. Kent Fire and Rescue Service and Norfolk County Council both point operators towards TR19-standard cleaning as evidence of a properly managed extract system.
There were over 2,500 fires in restaurants, cafes and public houses in 2011-12, according to government statistics cited by BESA. Around 70% of commercial kitchen fires originate in faulty extract ventilation because of fat and grease build-up, according to Kent Fire and Rescue Service. Enforcement officers can issue improvement notices or prohibition notices under the Fire Safety Order where ventilation systems are found uncleaned and uncertified.
How often should kitchen extract systems be cleaned under TR19?
TR19 sets cleaning frequency according to how intensively a kitchen extract system is used, measured in hours of operation per day. Heavy-use kitchens running 12 to 16 hours a day should be cleaned every three months, moderate-use kitchens running 6 to 12 hours every six months, and light-use kitchens running 2 to 6 hours every twelve months, according to BESA.
| Usage category | Hours of operation per day | Cleaning frequency |
|---|---|---|
| Heavy use | 12–16 hours | Every 3 months |
| Moderate use | 6–12 hours | Every 6 months |
| Light use | 2–6 hours | Every 12 months |
These bands are a starting point, not a ceiling. TR19 Grease also specifies that grease levels must never exceed a mean average of 200 microns between scheduled cleans, with any area reaching 500 microns or more requiring immediate spot cleaning regardless of the usual schedule, according to BESA.
A busy West End restaurant kitchen running double services seven days a week will sit firmly in the heavy-use band. A office staff canteen open for lunch only will usually fall into the light-use category, though a pre-clean inspection should always confirm the correct schedule rather than assuming it from opening hours alone.
Who is responsible for arranging TR19 cleaning — landlord, tenant or operator?
Responsibility for arranging TR19-compliant cleaning depends on the lease and who the Fire Safety Order 2005 names as the "responsible person" for that part of the building. In most commercial leases, the kitchen operator or tenant running the food business holds day-to-day responsibility, but the landlord retains responsibility for the shared ductwork and riser running through common parts.
This split causes genuine confusion on multi-let sites, particularly in mixed-use developments where several kitchens share a single extract riser. Facilities managers should check the lease's repairing covenants and the building's fire risk assessment to establish exactly where the dividing line sits, because insurers will ask for the cleaning certificate regardless of who commissioned the work.
Priority First has seen this ambiguity play out directly on complex sites. On a mixed-use West London development combining retail, residential and public areas, the client needed delivered-versus-promised duties made provable rather than assumed — the same principle that applies to TR19 responsibility, where "someone checks it" is not good enough without a documented owner and a paper trail.
What does a TR19-compliant clean involve, and what certification follows?
A TR19-compliant clean is a structured process that strips grease deposits from the entire extract pathway — canopy, ductwork, fan and discharge point — not just the visible canopy filters. The process typically runs through pre-clean inspection, isolation of electrics and gas, mechanical and chemical degreasing, verification of the cleaned surface, and reassembly with access panels resealed.
- Pre-clean inspection and risk assessment — the contractor surveys the system, measures existing grease thickness, and identifies access panels, fire dampers and any missing inspection hatches.
- Isolation — gas and electrical supplies to kitchen equipment are isolated before work begins, for safety and to protect equipment.
- Mechanical and chemical degreasing — technicians use rotary brushes, scrapers and BESA-specified degreasing agents to strip deposits from canopy, ductwork and fan internals.
- Verification — the cleaned surfaces are checked against the 200-micron mean average threshold, with photographic evidence taken before and after.
- Reassembly and certification — access panels are resealed, fire dampers tested, and a compliance certificate issued covering the date, scope, before/after grease readings and next due date.
The certificate issued afterwards should state the system's usage category, the grease thickness recorded, the access points cleaned and signed to, and a clear next-clean date. Insurers and fire enforcement officers will ask to see this document first in any post-incident review, so it needs to be retrievable, not filed away and forgotten.
What happens if extract systems are not cleaned to TR19 standard?
Failing to clean a kitchen extract system to TR19 standard raises the fire risk sharply and can invalidate insurance cover outright. Once a system is brought up to TR19 compliance, average total High Risk Combustion Load Levels can fall by 83%, according to Wikipedia, citing BESA TR19 guidelines — the reverse is also true, and an uncleaned system accumulates that risk steadily over time.
Insurers increasingly treat a valid TR19 certificate as a condition of cover for commercial kitchens, and a claim following a kitchen fire can be challenged or refused where no cleaning record exists. Enforcement under the Fire Safety Order 2005 can also follow a fire service inspection that finds grease-laden ductwork, potentially resulting in a prohibition notice that closes the kitchen until remedial works are completed.
The business cost runs beyond the fire itself. Lost trading days, reputational damage and the expense of emergency remedial cleaning after a near-miss typically dwarf the cost of a routine scheduled clean, which is precisely the argument every fire risk assessment under the Fire Safety Order is built to make.
How to check if a contractor is qualified for TR19 cleaning
A qualified TR19 contractor should be able to demonstrate specific training against the BESA specification, not simply general cleaning experience. BESA's TR19 toolkit describes the competence standard contractors should be trained against, and facilities managers should ask any prospective contractor for evidence of that training before commissioning work.
Beyond paperwork, a competent contractor will insist on a proper pre-clean survey rather than quoting blind, will photograph grease thickness before and after the clean, and will issue a certificate referencing the specific usage category and micron readings — not a generic "cleaned to industry standard" line. Contractors who skip the survey stage, who cannot explain the 200-micron threshold, or who offer no verification photographs should be treated as a red flag.
This is the same evidence discipline Priority First applies across its own facilities management and security operations. On an 11-officer deployment across a West London mixed-use site, every one of 152 checkpoints required a photograph — officer, GPS and timestamp attached — so that delivered cover was provable rather than asserted, with 540 or more patrols completed in the first five months. The same logic applies to any compliance contractor: proof on paper, not a promise over the phone.
TR19 vs TR19 Grease: what is the difference?
TR19 and TR19 Grease are related but distinct documents, and confusing the two is one of the most common compliance mistakes facilities managers make. TR19, properly called TR19 Air, is the general specification for internal cleanliness of ventilation ductwork across all building types; TR19 Grease is the stand-alone specification covering commercial kitchen extract systems specifically, separated out by BESA in 2020, according to the NBS Publication Index.
| Document | Scope | Key metric |
|---|---|---|
| TR19 Air | General ventilation ductwork, all building types | Visual cleanliness grading |
| TR19 Grease | Commercial kitchen extract systems | 200-micron mean average grease threshold |
A commercial kitchen needs TR19 Grease compliance for its extract canopy, ductwork and fan. The same building's office air-handling units, by contrast, fall under TR19 Air. Specifying the wrong document in a contract or lease schedule is a common drafting error that leaves facilities managers unsure which cleaning frequency and which certificate format actually applies.
Common mistakes businesses make with TR19 compliance
Several recurring errors undermine otherwise well-intentioned compliance programmes, and most stem from treating TR19 as a box-ticking exercise rather than an ongoing risk management duty.
- Assuming cleaning frequency from opening hours alone, rather than from a proper pre-clean survey that measures actual grease accumulation.
- Confusing TR19 Air with TR19 Grease in lease schedules and service contracts, leading to the wrong specification being quoted.
- Accepting a certificate with no micron readings, meaning there is no verifiable evidence the clean met the 200-micron threshold.
- Leaving access panel retrofits undone, which prevents a contractor reaching sealed sections of ductwork and forces partial, non-compliant cleans.
- Filing certificates where nobody can find them, so when an insurer or fire officer asks for proof after an incident, the paperwork cannot be produced quickly.
- Treating the landlord/tenant split as someone else's problem, leaving shared risers uncleaned because neither party believes it is their responsibility.
Multi-site operators face an added layer of complexity, since different units within the same portfolio often sit in different usage bands and need separately tracked schedules rather than one blanket cleaning date.
Your TR19 compliance checklist
- Confirm which usage category your kitchen falls into — heavy, moderate or light — based on actual daily operating hours.
- Book a pre-clean inspection with a contractor who measures existing grease thickness before quoting.
- Verify your contract specifies TR19 Grease, not general TR19 Air, if the job covers a kitchen extract system.
- Request micron readings and before/after photographs as part of every certificate issued.
- Check the lease to confirm whether landlord or tenant holds responsibility for shared extract risers.
- Store every certificate centrally and set a calendar reminder ahead of the next due date.
- Review your fire risk assessment under the Regulatory Reform (Fire Safety) Order 2005 to confirm kitchen extract is explicitly covered.
- Ask any prospective contractor for evidence of training against the BESA TR19 Grease specification before commissioning work.
FAQ
What is TR19 and who publishes it?
TR19 is a technical cleanliness specification for ventilation systems published by BESA, the Building Engineering Services Association. The current kitchen-specific version, TR19 Grease, was separated into its own document in 2020, according to the NBS Publication Index.
Is TR19 kitchen extract cleaning a legal requirement in the UK?
TR19 itself is an industry specification rather than a statute, but the underlying legal duty comes from the Regulatory Reform (Fire Safety) Order 2005, which requires the "responsible person" to assess and manage fire risk from kitchen extract systems. Fire authorities such as Kent Fire and Rescue Service treat TR19 compliance as the recognised way of meeting that duty.
How often does TR19 require kitchen extract cleaning?
TR19 sets cleaning frequency by usage: every three months for heavy use (12–16 hours a day), every six months for moderate use (6–12 hours a day), and every twelve months for light use (2–6 hours a day), according to BESA.
What is the 200-micron rule in TR19 Grease?
TR19 Grease specifies that grease deposits must not exceed a mean average of 200 microns between scheduled cleans. Any area reaching 500 microns or more requires immediate spot cleaning rather than waiting for the next scheduled visit, according to BESA.
Do insurers require TR19 certification for commercial kitchens?
Many commercial insurers treat a valid TR19 certificate as a condition of cover or as key evidence in a post-fire claim. An uncleaned or uncertified extract system is one of the most common reasons insurers challenge kitchen fire claims.
What should a TR19 compliance certificate include?
A proper certificate should state the cleaning date, the system's usage category, the measured grease thickness before and after cleaning, the access points worked on, and the next due date. A certificate without micron readings offers limited protection in an insurance dispute or fire investigation.
What is the difference between TR19 Air and TR19 Grease?
TR19 Air covers general ventilation ductwork cleanliness across all building types, while TR19 Grease is the specific standard for commercial kitchen extract systems, introduced as a stand-alone document by BESA in 2020, according to the NBS Publication Index.
Protecting your kitchen and building with Priority First
Kitchen extract compliance rarely sits in isolation — it is one strand of a wider fire safety and building management duty that facilities managers carry across an entire site, and a missed TR19 clean is exactly the kind of gap that surfaces during an insurance review or fire inspection. Priority First brings the same evidence-first discipline it applies to security patrols — photographed, timestamped, auditable — to the wider compliance picture across the commercial and residential buildings it manages.
Priority First protects over £1.6 billion in client assets across prime central London, West London, the West Midlands and Bedfordshire, working across construction, commercial, luxury retail, hotel and residential estates, as published in the Estates Gazette advertisement feature of November 2026. That same accountability extends to building compliance: where cleaning certificates, fire risk assessments and maintenance records need to be centrally tracked, provable and ready for an insurer or enforcement officer on demand.
If your building's kitchen extract compliance, fire risk assessment or wider facilities management needs a single accountable partner, speak to Priority First's facilities management team about a compliance review.
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