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Kitchen extraction cleaning - audits and compliance
A kitchen thought its extraction was being cleaned - there were invoices, a cleaner came. Then a proper audit looked inside the ductwork and found years of missed or superficial cleaning: grease-laden duct that had never really been done. It is a common and alarming discovery. Here is why audits find years of missed cleaning, and what it means for your fire risk. This is general commentary.
The short answer
It is a surprisingly common and alarming discovery: a kitchen believes its extraction system has been cleaned regularly - there are cleaning invoices, a cleaner has been coming - and then a proper audit or survey looks inside the ductwork and finds years of missed or superficial cleaning: the ductwork heavily grease-laden, evidently never properly cleaned, despite the apparent cleaning history. How this happens: the cleaning that was done was superficial - the visible parts (the canopy, the filters, the accessible surfaces) were cleaned, giving the appearance of a cleaned system, but the ductwork (the enclosed duct runs where grease build-up is the real fire risk) was not properly cleaned - perhaps because there was no access to it, or the cleaner did not do it, or only did what was easy. And crucially, this was never verified: no one inspected inside the ductwork to confirm it was actually clean. So the invoices and visits gave false reassurance - they showed cleaning was paid for and happened, but not that the ductwork was genuinely cleaned. Over years, the ductwork grease built up unseen, until an audit (a proper internal inspection, often with photographs and grease-thickness measurement to the TR19 Grease standard) revealed it. Why audits find it: because an audit does what routine cleaning invoices do not - it inspects inside the ductwork, where the grease hides and the fire risk lives, and measures against the standard, exposing the gap between the apparent cleaning and the actual state. What it means: years of missed ductwork cleaning means a heavy grease build-up - a serious, hidden fire risk (grease in ductwork being a recognised cause of severe kitchen fires) - that needs a proper, thorough deep clean to remove, and then a verified, TR19-compliant cleaning regime (with internal inspection and proof) to prevent it recurring. So the audit that found years of missed cleaning is a common story with a serious lesson: verify what is actually being cleaned inside the duct, not just that cleaning happened. This is general commentary on extraction cleaning and fire risk.
Key points
The discovery
The story is common: a kitchen believes its extraction is being cleaned regularly, and then a proper audit finds it has not really been cleaned for years. The kitchen has what looks like a cleaning history - invoices for extraction cleaning, a cleaner who has been coming - so it believes the system is maintained. Then something prompts a proper look: a new fire risk assessment, an insurer's requirement, a change of management, or a specialist survey - and an audit inspects inside the ductwork. What it finds is alarming: the ductwork heavily grease-laden, evidently never properly cleaned, despite the apparent history. Years of grease build-up that the cleaning was supposed to have prevented.
This is a genuinely common discovery, and an alarming one - because the kitchen believed it was compliant and safe (it was paying for cleaning), and finds it has a serious, long-standing grease build-up and fire risk instead. The gap between the belief (regularly cleaned) and the reality (years of missed ductwork cleaning) is the heart of the story. It raises the questions the following sections address: how could this happen despite the cleaning invoices (superficial cleaning, never verified), why did an audit find what the routine cleaning missed (it inspected inside the duct), and what does it mean (a serious hidden fire risk to remove and prevent). So the discovery is a kitchen believed clean, found grease-laden - a common, alarming gap between apparent and actual cleaning. So believed clean, found grease-laden, is the discovery. This is general commentary.
How it happens
Years of missed cleaning despite a cleaning history happens for two reasons: the cleaning that was done was superficial (the visible parts, not the ductwork), and it was never verified (no one checked inside the duct). Superficial cleaning: 'extraction cleaning' can mean very different things. A proper, TR19-compliant clean cleans the whole system, including the ductwork throughout (where grease build-up is the real fire risk). But a superficial 'clean' cleans only the visible, easy parts - the canopy, the filters, the accessible surfaces - leaving the enclosed ductwork untouched. This gives the appearance of a cleaned system (the visible parts look clean) while the ductwork stays grease-laden. This can happen because there was no access to the ductwork (no access panels), because the cleaner only did the canopy and filters (a cheaper, easier job), or because the buyer did not know the difference (as covered in why a canopy clean alone isn't TR19 compliant).
Never verified: crucially, no one inspected inside the ductwork to confirm it was actually clean. The kitchen took the invoices and the cleaner's visits as proof the system was cleaned - but invoices and visits prove cleaning was paid for and happened, not that the ductwork was genuinely cleaned to standard. Without internal inspection (looking inside the duct, ideally with photographs and grease measurement), there was no check on what was actually being cleaned - so the superficial cleaning went unquestioned, year after year, while the ductwork grease built up unseen. So it happens through superficial cleaning (visible parts only) that was never verified (no internal check) - the two together allowing years of missed ductwork cleaning behind an apparent cleaning history. So superficial cleaning, never verified, is how it happens. This is general commentary.
Why the audit found it
The audit found what the routine cleaning history hid because an audit does what invoices and visits do not: it inspects inside the ductwork, where the grease hides and the fire risk lives, and measures against the standard. A proper extraction audit or survey is an inspection of the actual condition of the system - opening or inspecting inside the ductwork (through access panels, or with inspection cameras), looking at the internal surfaces where grease builds up, often photographing them and measuring the grease thickness (against the TR19 Grease standard's criteria). So it looks at the reality inside the duct, not the paperwork or the visible surfaces.
This is exactly what reveals years of missed cleaning: the audit sees the heavy grease build-up on the internal duct surfaces - build-up that could only have accumulated if the ductwork had not been properly cleaned for a long time - exposing the gap between the apparent cleaning (invoices, visible clean) and the actual state (grease-laden duct). Where the routine cleaning history gave false reassurance (cleaning happened, so it must be clean), the audit gives the truth (here is the grease inside). So the audit found the missed cleaning because it inspected inside the duct - the one place that shows whether the ductwork has really been cleaned. This is why audits and internal inspections matter: they verify the actual condition, catching the superficial-cleaning gap that invoices and visible cleaning hide. So the audit found it by inspecting inside the duct. So it inspected inside the duct, where the truth is. This is general commentary.
What it means
What years of missed ductwork cleaning means is serious: a heavy grease build-up in the ductwork, which is a significant, hidden fire risk that has been accumulating unnoticed. Grease build-up in extract ductwork is combustible and a recognised cause of serious kitchen fires - a grease fire in the duct can spread rapidly through the system and to the building. So a heavy build-up from years of missed cleaning is a real and serious fire hazard, sitting hidden in the ductwork, that the kitchen did not know it had (believing the system cleaned). It is also a compliance and insurance exposure - the system has not been maintained to standard (despite the appearance), which matters for the fire risk assessment and potentially for insurance cover.
So the discovery, alarming as it is, is important to have made - because it reveals a serious hidden risk that can now be addressed. What it means practically: the built-up grease needs to be removed by a proper, thorough deep clean of the whole system (including the neglected ductwork) - which may be a bigger job than a routine clean, given the accumulation, and may require adding access panels to reach the previously inaccessible duct. And then a verified, TR19-compliant cleaning regime needs to be put in place - proper whole-system cleaning at the right frequency, with internal inspection and proper records (report, logbook, photographs) - so the ductwork is genuinely cleaned going forward, verified, not just apparently. So what it means is a serious hidden fire risk to remove (a proper deep clean) and prevent (a verified regime). So it means a serious hidden fire risk, now to be addressed. This is general commentary.
Verify what is cleaned
So the audit that found years of missed cleaning is a common story with a clear lesson: verify what is actually being cleaned inside the ductwork, not just that cleaning happened. A kitchen can have cleaning invoices and a cleaner's visits and still have a grease-laden, uncleaned ductwork and a serious hidden fire risk - because superficial cleaning, never verified against the inside of the duct, leaves the ductwork undone behind an apparent cleaning history. The audit reveals this by inspecting inside the duct - and the lesson is to ensure your extraction cleaning is genuine and verified. So verify what is cleaned, not just that cleaning happened.
This connects to what a proper extraction clean and a proper cleaning regime involve. A genuine extraction clean cleans the whole system - including the ductwork throughout - to remove the grease that is the fire risk, and verifies it (internal inspection, photographs, grease measurement, a proper report and logbook) so you have proof of what was actually cleaned and its condition. This is what distinguishes a real clean from a superficial one, and what prevents the years-of-missed-cleaning situation: the whole system is genuinely cleaned, and the internal condition is inspected and documented, so there is no hidden gap. So the answer to the audit's discovery - and the way to avoid being the next such story - is a proper, whole-system extraction clean, verified with internal inspection and records, at the right frequency. Rather than trusting that cleaning happened, you verify what was cleaned. So verify what is cleaned inside the duct, through a proper, documented whole-system clean. This is general commentary on extraction cleaning and fire risk.
Questions
Because the cleaning that was done was superficial (the visible parts, not the ductwork) and was never verified against the inside of the duct - so invoices and visits gave false reassurance. 'Extraction cleaning' can mean very different things: a proper, TR19-compliant clean cleans the whole system including the ductwork (where grease build-up is the real fire risk), but a superficial clean cleans only the visible, easy parts (the canopy, filters, accessible surfaces), leaving the enclosed ductwork untouched - while looking, from the visible parts, like a cleaned system. This can happen because there was no access to the ductwork, because the cleaner only did the canopy and filters, or because the buyer did not know the difference. And crucially, no one inspected inside the ductwork to confirm it was actually clean - so the invoices and visits (which prove cleaning was paid for and happened, not that the ductwork was genuinely cleaned) went unquestioned, while the ductwork grease built up unseen for years. So cleaning can be missed for years despite invoices when it was superficial and never verified. So invoices don't prove the ductwork was cleaned. This is general commentary.
The actual condition inside the ductwork - inspecting the internal surfaces where grease builds up, often with photographs and grease-thickness measurement against the TR19 Grease standard. A proper extraction audit or survey is an inspection of the real condition of the system: opening or inspecting inside the ductwork (through access panels, or with inspection cameras), looking at the internal surfaces where grease accumulates, photographing them, and measuring the grease thickness against the standard's criteria. So it examines the reality inside the duct, not the paperwork or just the visible surfaces. This is what reveals whether the ductwork has really been cleaned: a heavy grease build-up on the internal surfaces shows the ductwork has not been properly cleaned for a long time, exposing any gap between the apparent cleaning (invoices, visible clean) and the actual state. So an audit checks the actual internal condition of the system - the one thing that shows whether the ductwork is genuinely clean - which is why it can find years of missed cleaning that invoices and visible cleaning hid. So an audit checks inside the duct against the standard. This is general commentary.
Because grease build-up in extract ductwork is a serious, recognised fire risk - so years of missed cleaning means a heavy, hidden fire hazard. Grease in extract ductwork is combustible, and a grease fire in the duct can spread rapidly through the system and to the building - it is a recognised cause of serious kitchen fires. So a heavy build-up from years of missed cleaning is a real and serious fire hazard, sitting hidden in the ductwork, that the kitchen did not know it had (believing the system cleaned). It is also a compliance and insurance exposure: the system has not been maintained to standard despite the appearance, which matters for the fire risk assessment and potentially for insurance cover (an insurer may expect the extraction cleaned to standard, and neglect could affect a claim). So missed ductwork cleaning is serious because it leaves a significant, hidden fire risk (and a compliance/insurance gap) that has been accumulating unnoticed. This is why discovering it, alarming as it is, matters - the risk can then be addressed. So it is serious because of the hidden grease fire risk. This is general commentary.
Remove it with a proper, thorough deep clean of the whole system, then put a verified, TR19-compliant cleaning regime in place to prevent it recurring. First, the built-up grease needs removing by a thorough deep clean of the whole system, including the neglected ductwork - which may be a bigger job than a routine clean, given the accumulation, and may require adding access panels to reach previously inaccessible duct (so it can all be cleaned). This clears the immediate fire risk. Then, a proper ongoing regime needs establishing: whole-system cleaning at the right frequency (matched to the cooking volume), with internal inspection and proper records (report, logbook, photographs, grease measurement) - so the ductwork is genuinely cleaned going forward, and verified, not just apparently. This prevents the situation recurring. So after an audit finds heavy build-up: deep clean the whole system to remove it (adding access where needed), then maintain a verified, compliant regime. This turns the alarming discovery into a resolved risk and a properly-maintained system. So remove it with a full deep clean, then maintain a verified regime. This is general commentary.
By ensuring your extraction cleaning is genuine (the whole system, including the ductwork) and verified (with internal inspection and records) - not just trusting that cleaning happened. The years-of-missed-cleaning situation arises from superficial cleaning that was never verified. To avoid it: use a competent extraction cleaner who cleans the whole system to the TR19 Grease standard (including the ductwork, not just the canopy and filters); ensure there is adequate access (access panels) so the whole duct can be reached and cleaned; and insist on verification - internal inspection of the ductwork, with photographs, grease measurement, and a proper report and logbook - so you have proof of what was actually cleaned and its condition, not just an invoice. Clean at the right frequency for your cooking volume. So rather than trusting that cleaning happened (invoices and visits), verify what was cleaned (the internal condition, documented). This is what distinguishes a real, verified clean from a superficial, unverified one - and what prevents a hidden grease build-up accumulating unseen. So avoid it by ensuring genuine, whole-system, verified cleaning. This is general commentary.
No - invoices and cleaner visits prove that cleaning was paid for and happened, but not that the ductwork was genuinely cleaned to standard. This is the crux of how years of missed cleaning happen despite an apparent cleaning history: a kitchen takes the invoices and visits as proof the system is cleaned, but they only show cleaning of some kind occurred - not what was actually cleaned. A superficial clean (canopy and filters only) generates the same invoices and visits as a proper whole-system clean, but leaves the ductwork grease-laden. So without verification of the actual internal condition, invoices and visits give false reassurance. What does prove the ductwork is being cleaned is verification: internal inspection of the ductwork (photographs, grease measurement) and a proper report and logbook documenting the whole-system clean and the condition - proof of what was actually done inside the duct, not just that a cleaner came. So no - invoices and visits do not prove the ductwork is cleaned; only internal inspection and proper records do. This is why verified cleaning matters. So invoices and visits are not proof; verification is. This is general commentary.
Years of missed ductwork cleaning leave a serious hidden fire risk. Our extraction cleaning cleans the whole system - ductwork included - to TR19 Grease, verified with internal inspection, photographs and a logbook, so you know what was actually cleaned, not just that cleaning happened. Ask us to audit and clean your system properly.
