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Kitchen extraction cleaning - inspection
A lingering smell that an inspector notices is a sign of an underlying problem - and masking it won't pass. A kitchen failing on smell usually has a real, persistent odour source: stale grease in the extraction, smelly drains, or a cleaning shortfall. Here is why a kitchen fails on smell at inspection, and how to find and fix the source. This is general guidance, not inspection advice.
The short answer
Failing (or being marked down) on smell at an inspection is frustrating - and it can feel unfair if the kitchen looks clean. But a smell an inspector notices is a genuine signal, and the answer is to find and fix its source. Here's why a kitchen fails on smell, and what to do. This is general guidance, not inspection advice; the inspection regime sets the standards. A smell signals an underlying problem. First, why a smell matters at inspection: a persistent smell is a sign of an underlying problem - something not clean, not maintained, or not right. An inspector judges the cleanliness and condition of the kitchen, and a lingering odour indicates a source (decomposing grease, food, waste, or drainage) that hasn't been dealt with. So a smell isn't just an unpleasant impression - it points to a real issue, which is why it can cost you at inspection. And it means masking the smell won't pass: an air freshener doesn't fix the underlying problem (and inspectors see through masking). The common sources. A persistent kitchen smell usually traces to one (or more) of a few real sources: Stale grease in the extraction. Grease built up in the hidden ductwork and fan decomposes over time and gives off a stale, greasy smell, carried out when the extraction runs (as covered in the smell-of-stale-grease and canopy-clean-but-still-smells pages). So a grease-laden, under-cleaned extraction is a common source of a persistent kitchen odour - and one that a clean-looking kitchen can still have (the grease is hidden). Smelly drains. Grease and food building up in the drains, gullies and grease trap decompose and smell - a classic source of a persistent kitchen odour, and a drainage-maintenance issue (as covered in the why-do-my-kitchen-drains-smell page). General cleaning shortfalls. Areas not being cleaned properly - behind and under equipment, spillages, food debris left, waste not managed - can harbour odour. So the smell usually traces to the extraction, the drains, or a cleaning gap (or a combination). Find the source. So the way to fix a smell is to find its real source - by where it's strongest, what it's like, and when it occurs: Strongest near the canopy, or when the extraction runs? Points to the extraction (stale grease in the duct). Strongest at the drains, gullies or sink, or sewer-like? Points to the drains. Localised to a particular area or equipment? Points to a cleaning gap there. A stale, greasy smell can be the extraction or the drains (both grease); a rotting/sewer smell leans to drains; a specific area smell points to cleaning. So identify which source(s) apply. Fix the source. Then address the actual source(s): Clean the extraction - a proper clean of the hidden ductwork and fan removes the stale grease (if that's the source). Maintain the drains - clean the drains, gullies and grease trap, and manage the grease trap (if the drains are the source). Tighten the cleaning - clean the neglected areas properly and manage waste (if a cleaning gap is the source). So you fix the cause, and the smell genuinely goes - which is what passes an inspection (a genuinely clean, odour-free kitchen), not masking. Don't just mask it. It's worth stressing: don't just mask the smell (air fresheners, etc.) to try to pass. The inspector is judging the underlying cleanliness and condition, so a masked smell doesn't fix the problem (and often returns, or is seen through). Masking might hide the smell briefly but leaves the underlying issue (the grease, the drains, the cleaning gap) - which will show up again (and the source, like grease-laden ducts, may be a fire-safety or hygiene problem in its own right). So fix the source, don't mask. The takeaway. So a kitchen fails on smell at inspection because a persistent odour from a real source (stale grease in the extraction, smelly drains, or a cleaning shortfall) is present - a sign of an underlying problem. The fix is to find the source and address it (clean the extraction, maintain the drains, tighten the cleaning), not mask it. So find the real source and fix it. This is general guidance, not inspection advice.
Key points
A smell signals a problem
A persistent smell that an inspector notices is a sign of an underlying problem - something not clean, not maintained, or not right. An inspector judges the cleanliness and condition of the kitchen, and a lingering odour indicates a source (decomposing grease, food, waste, or drainage) that hasn't been dealt with. So a smell isn't just an unpleasant impression to the inspector - it points to a real issue, which is why it can cost you at inspection.
This is the key to understanding why you're failing on smell: the smell is a symptom of a real source, and the inspector is (rightly) treating it as a sign of an underlying problem. So the smell isn't the problem itself - it's the signal of the problem (the grease, drains or cleaning gap causing it). And crucially, this means masking the smell won't pass: an air freshener doesn't fix the underlying source (and inspectors see through masking). So the way to pass is to find and fix the real source, not cover up the smell. So a smell signals a problem - it points to a real source - is the framing: treat the smell as a symptom to trace to its cause, which the following sections cover (the common sources, finding them, and fixing them). So the smell is a symptom of a real source to find. This is general guidance, not inspection advice.
The common sources
A persistent kitchen smell usually traces to one (or more) of a few real sources. Stale grease in the extraction: grease built up in the hidden ductwork and fan decomposes over time and gives off a stale, greasy smell, carried out when the extraction runs (as covered in the smell-of-stale-grease and why-is-my-canopy-clean-but-the-system-still-smells pages). So a grease-laden, under-cleaned extraction is a common source - and one a clean-looking kitchen can still have (the grease is hidden). Smelly drains: grease and food building up in the drains, gullies and grease trap decompose and smell - a classic source of a persistent kitchen odour, and a drainage-maintenance issue (as covered in the why-do-my-kitchen-drains-smell page).
General cleaning shortfalls: areas not being cleaned properly - behind and under equipment, spillages, food debris left, waste not managed - can harbour odour. So the smell usually traces to the extraction (stale hidden grease), the drains (grease and food in the drainage), or a cleaning gap (neglected areas) - or a combination of these. These are the real sources behind a persistent kitchen smell. Identifying which one(s) apply is the next step (covered below), because it determines the fix. So the common sources - extraction, drains, or a cleaning gap - are what a smell at inspection usually comes from. So the smell comes from the ducts, the drains, or a cleaning gap. This is general guidance, not inspection advice.
Find the source
To fix a smell, find its real source - by where it's strongest, what it's like, and when it occurs. Where is it strongest? A smell strongest near the canopy, or that comes when the extraction runs, points to the extraction (stale grease in the duct); a smell strongest at the drains, gullies or sink points to the drains; a smell localised to a particular area or piece of equipment points to a cleaning gap there. What's it like? A stale, greasy smell can be the extraction or the drains (both are grease); a rotting-food or sewer-like smell leans toward the drains; a specific area smell points to cleaning.
When does it occur? A smell that comes with the extraction running suggests the duct; a smell when water drains or from unused traps suggests the drains; a constant smell in one area suggests a cleaning gap. So use where, what and when to identify the source(s) of the smell - the extraction, the drains, or a cleaning gap (or a mix). This is the same diagnostic approach as telling a drain smell from a duct smell (as covered in the why-do-my-kitchen-drains-smell page), extended to include cleaning gaps. Getting the source right means you fix the actual cause rather than the wrong thing. So find the source - where, what, and when the smell is - is the diagnostic step: identify what's actually causing the smell before fixing it. So trace the smell to its real source. This is general guidance, not inspection advice.
Fix the source
Once you've identified the source(s), address them. Clean the extraction: if the source is stale grease in the hidden ductwork and fan, a proper extraction clean (to the TR19 Grease standard, reaching the hidden parts) removes the stale grease and clears that smell. Maintain the drains: if the source is the drains, clean the drains, gullies and grease trap and manage the grease trap (drainage maintenance) to remove the grease and food causing the smell. Tighten the cleaning: if the source is a cleaning gap, clean the neglected areas properly (behind and under equipment, spillages) and manage waste - closing the gap.
So you fix the actual cause of the smell - and the smell genuinely goes, which is what passes an inspection (a genuinely clean, odour-free kitchen). Often more than one source is involved, so you may need to address several (clean the extraction and maintain the drains and tighten the cleaning). The point is to deal with each real source, so the odour is removed at its cause. This also addresses the underlying problems the smell signalled (a grease-laden duct is a fire risk, smelly drains a hygiene issue, a cleaning gap a hygiene issue) - so fixing the source improves the kitchen, not just the smell. So fix the source - clean the duct, the drains, or the gap - is the remedy: address whichever real source(s) the smell traces to, removing the odour at its cause. So fix the actual source(s) of the smell. This is general guidance, not inspection advice.
Don't just mask it
It's worth stressing: don't just mask the smell (air fresheners and the like) to try to pass. The inspector is judging the underlying cleanliness and condition of the kitchen, so a masked smell doesn't fix the problem - and often returns, or is seen through. Masking might hide the smell briefly, but it leaves the underlying issue (the grease, the drains, the cleaning gap) in place - which will show up again (the smell returning, or the source being found), and which is often a real problem in its own right (grease-laden ducts are a fire and hygiene issue; smelly drains and cleaning gaps are hygiene issues).
So masking is not a solution - it's an attempt to hide a symptom while the cause remains. It doesn't pass a proper inspection (the inspector assesses the underlying condition, not just the immediate smell), and it leaves you with the real problem. The only genuine fix is to address the source, so the smell goes because its cause is gone. So don't just mask it - masking won't pass an inspection - is the closing caution: resist the temptation to cover up the smell, and instead find and fix the real source (the extraction, the drains, or the cleaning), so your kitchen is genuinely clean and odour-free, which is what passes. So fix the cause, don't mask the symptom. So address the real source, not the smell alone. This is general guidance, not inspection advice.
Questions
Because a persistent odour is present that signals an underlying problem - usually stale grease in the extraction, smelly drains, or a cleaning shortfall; the inspector treats the smell as a sign of something not clean or not right. A kitchen fails (or is marked down) on smell at inspection because a persistent odour is present, and a lingering smell signals an underlying problem - something not clean, maintained or right. The inspector judges the kitchen's cleanliness and condition, so a smell indicates a real source that hasn't been dealt with. The common sources: stale grease in the hidden extraction ductwork and fan (decomposing and giving off a stale smell); smelly drains (grease and food building up in the drains and grease trap); and general cleaning shortfalls (neglected areas, spillages, waste harbouring odour). So the smell usually traces to the extraction, the drains, or a cleaning gap. The way to pass is to find and fix the real source, not mask the smell (masking doesn't fix the cause and won't fool an inspector). So because a real odour source signals an underlying problem. So a real source - duct, drains or cleaning - the inspector noticed. This is general guidance, not inspection advice.
Yes - grease built up in the hidden ductwork and fan decomposes and gives off a stale, greasy smell (carried out when the extraction runs), so a grease-laden, under-cleaned extraction is a common odour source, even in a clean-looking kitchen. Yes - the extraction can be a source of a smell that fails an inspection. Grease built up in the hidden ductwork and fan decomposes over time and gives off a stale, greasy smell, which the airflow carries out when the extraction runs. So a grease-laden, under-cleaned extraction is a common source of a persistent kitchen odour. Importantly, this can happen even in a clean-looking kitchen - the grease causing the smell is in the hidden ductwork (out of sight), so the visible surfaces can be clean while the hidden system smells (as covered in the why-is-my-canopy-clean-but-the-system-still-smells page). So if you're failing on smell and the smell is stale and greasy (especially strongest near the canopy or when the extraction runs), the extraction is a likely source. The fix is a proper extraction clean of the hidden ductwork and fan, removing the stale grease at the cause. So yes - stale grease in the hidden ductwork is a common cause. So yes; a grease-laden duct can smell. This is general guidance, not inspection advice.
By where it's strongest (canopy/extraction vs drains vs a specific area), what it's like (stale grease vs sewer vs localised), and when it occurs (with the extraction running vs when water drains) - which points to the extraction, the drains, or a cleaning gap. To find the source of a kitchen smell, use where it's strongest, what it's like, and when it occurs. Where: a smell strongest near the canopy or when the extraction runs points to the extraction (stale duct grease); strongest at the drains, gullies or sink points to the drains; localised to a particular area or equipment points to a cleaning gap there. What: a stale, greasy smell can be the extraction or the drains (both grease); a rotting-food or sewer-like smell leans to the drains; a specific-area smell points to cleaning. When: a smell with the extraction running suggests the duct; a smell when water drains suggests the drains; a constant area smell suggests a cleaning gap. So use where, what and when to identify the source(s) - the extraction, the drains, or a cleaning gap (or a mix). Getting the source right means you fix the actual cause. So trace it by location, character and timing. So by where it's strongest, what it smells like, and when. This is general guidance, not inspection advice.
Find and fix the real source - clean the extraction (if stale duct grease), maintain the drains and grease trap (if the drains), and tighten the cleaning (if a cleaning gap) - so the smell genuinely goes; a genuinely clean, odour-free kitchen is what passes. To fix a smell so you pass inspection, address the real source(s) - which requires identifying them first (by where, what and when). Then: clean the extraction if the source is stale grease in the hidden ductwork and fan (a proper clean to TR19 Grease, removing the grease at the cause); maintain the drains if the source is the drains (clean the drains, gullies and grease trap - drainage maintenance); and tighten the cleaning if the source is a cleaning gap (clean the neglected areas properly, manage waste). Often more than one source is involved, so you may need to address several. By fixing the actual cause(s), the smell genuinely goes - which is what passes an inspection (a genuinely clean, odour-free kitchen). Don't try to mask the smell (air fresheners); the inspector judges the underlying condition, so masking won't pass and leaves the real problem. So fix the source, so the kitchen is genuinely odour-free. So clean the duct, drains or gap causing it. So find and fix the real source. This is general guidance, not inspection advice.
No - masking won't pass; the inspector judges the underlying cleanliness, so a masked smell doesn't fix the problem (and often returns or is seen through), leaving the real source - which may be a fire or hygiene issue - in place. No - you can't just use air freshener to pass. Masking the smell doesn't fix the underlying problem: the inspector is judging the kitchen's underlying cleanliness and condition, so a masked smell doesn't address the real source (the grease, drains or cleaning gap) - and often the masking is seen through, or the smell returns once the freshener fades. Worse, masking leaves the real problem in place: a grease-laden extraction (a fire and hygiene issue), smelly drains (a hygiene issue), or a cleaning gap (a hygiene issue). So masking is hiding a symptom while the cause - which is itself often a genuine problem - remains. It's not a solution and won't reliably pass a proper inspection. The only genuine fix is to address the source, so the smell goes because its cause is gone (a genuinely clean, odour-free kitchen). So don't rely on air freshener - find and fix the real source. So no - masking won't pass and leaves the problem. So no; fix the source instead. This is general guidance, not inspection advice.
It can be - a stale grease smell means a grease-laden extraction (a fire and hygiene concern), and smelly drains or cleaning gaps are hygiene concerns; so the smell's source is often a real problem beyond the inspection, worth fixing anyway. Yes - the source of a smell is often a real fire-safety or hygiene issue in its own right, so fixing it matters beyond just passing the inspection. If the smell is stale grease from the hidden extraction, that means the ductwork is grease-laden - which is a fire risk (the grease fuels duct fires) as well as an odour and hygiene concern. If the smell is from the drains, that's a hygiene issue (decomposing grease and food in the drainage). If it's from a cleaning gap, that's a hygiene issue (neglected areas harbouring dirt and odour). So the smell is signalling an underlying problem that's often genuinely important - not just an inspection nicety. This is another reason to fix the source rather than mask the smell: addressing the cause (cleaning the extraction, maintaining the drains, tightening the cleaning) resolves a real fire-safety or hygiene problem, not just the smell. So the smell's source is usually worth fixing regardless of the inspection. So yes - the source is often a real fire or hygiene issue. So yes; fixing it matters anyway. This is general guidance, not inspection advice.
Stale grease in the hidden ductwork is a common cause of a persistent kitchen smell; if the extraction is the source, we clean the whole system to TR19 Grease, removing the decomposing grease at the cause of the smell - not masking it. Ask us to check and clean your extraction if a smell persists. This is general guidance, not inspection advice.
