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Extraction cleaning - survey and assessment
Before a kitchen extraction system is cleaned - or a cleaning schedule is set - it helps to know what state it is actually in. That is what a grease loading survey is for: it assesses how much grease has built up, how well the system can be reached to clean it, and how often it needs cleaning. Here is what a grease loading survey measures, and why it is the sensible first step.
The short answer
A grease loading survey measures three connected things. First, the grease build-up: how much grease has accumulated through the system, measured objectively - in microns, with a comb gauge - at points along the ducts, canopy and fan, to see how loaded the system is and where the worst build-up is. Second, the access: how well the system can be reached for cleaning - where the access panels are, whether there are enough of them, and whether any sections are effectively unreachable. Third, the cleaning frequency: based on the grease level and how fast the system loads, how often the system needs cleaning to keep the grease under control. Together, these give you a clear picture of the system's state and what it needs - which is why a survey is the sensible first step before cleaning or setting a schedule.
How much grease, and where
The core thing a grease loading survey measures is the grease build-up itself - how much grease has accumulated in the system, and where. This is done objectively, by measuring the grease depth in microns with a comb gauge at points along the system: the canopy, through the duct runs, at bends and low points where grease collects, and at the fan. Rather than a subjective glance, the survey produces actual figures for how thick the grease is at each point, which can be read against the recognised thresholds to judge whether the level is acceptable or whether cleaning is due. So the survey turns the hidden state of the grease inside the ducts into measured data.
Measuring at multiple points matters because grease builds up unevenly - heavier in some places than others - so the survey maps the build-up through the system rather than assuming it is uniform. This shows not just the overall level but where the worst accumulations are: the high spots that may need particular attention. So the grease-loading part of the survey tells you two things - how loaded the system is on average, and where the heaviest build-ups are - both of which matter for judging what the system needs. It is the objective measurement of the grease that makes the survey more than a guess: it establishes, in figures, how much grease is actually there and where.
How well it can be reached
The second thing a grease loading survey measures is the access - how well the system can actually be reached for cleaning. A duct full of grease is only cleanable if a cleaner can get to the inside of it, and that depends on access panels: the openings that let the ductwork be entered and cleaned. The survey assesses where the access panels are, whether there are enough of them, and whether they are positioned so that the whole run can be reached - or whether there are sections that no panel gives access to, which would be effectively impossible to clean properly without additional panels being fitted. So the survey is checking not just how dirty the system is, but how cleanable it is.
This matters because access problems are common and consequential. A system with too few access panels, or panels poorly placed, can have sections that never get properly cleaned because no one can reach them - and those sections accumulate grease and fire risk unchecked. The survey uncovers this, showing where the access is adequate and where it is not, so that any access shortcomings can be addressed - typically by fitting additional access panels - before or as part of cleaning. So the access assessment is a crucial part of the survey: it establishes whether the system can be cleaned throughout, or whether work is needed to make it fully cleanable. Without it, a clean might leave unreachable sections loaded with grease, with no one aware.
How often it needs cleaning
The third thing a grease loading survey measures - or rather, determines - is how often the system needs cleaning. Cleaning frequency is not one-size-fits-all: it depends on how fast the particular system loads with grease, which depends on the cooking. A high-output kitchen doing a lot of frying and grilling loads its ducts with grease far faster than a light-use kitchen, so it needs cleaning much more often. The survey, by measuring the current grease level and taking account of the cooking and usage, informs how frequently the system needs cleaning to keep the grease under the acceptable level - so the cleaning schedule fits the actual system rather than a generic assumption.
This is valuable because it puts the cleaning schedule on a rational footing. Rather than cleaning too rarely and letting the grease and fire risk build up dangerously, or too often and paying for cleaning the system does not yet need, the frequency is set to match how the system actually loads. The survey provides the basis for that: a measured starting point and an assessment of the loading rate, from which a sensible interval can be set. So the frequency determination turns the survey from a one-off snapshot into the basis for ongoing management - it tells you not just what the system needs now, but how often it will need cleaning going forward. That is what makes the survey a foundation for keeping the system safe over time.
Why the survey comes first
Putting the three together - the grease level, the access, and the frequency - shows why a grease loading survey is the sensible first step before cleaning or setting a schedule. It gives you a clear, measured picture of the system's state and needs: how much grease is there and where, whether the system can be reached to clean it, and how often it needs cleaning. With that picture, cleaning can be done properly - targeting the worst build-ups, addressing any access shortcomings, and on a sensible interval - rather than blindly. Without it, you are cleaning without knowing the state you are starting from or whether you can even reach all of it.
The survey is also the basis for demonstrating that the system is being managed. The measured grease levels, the access assessment and the cleaning frequency it establishes are a documented picture of the system that shows the grease is being assessed and controlled - useful for a duty holder needing to show their extraction system is maintained. So the survey serves both the practical job of guiding the cleaning and the management job of evidencing it. That is why it comes first: it establishes what the system is, what it needs, and how it will be kept under control - the foundation on which sensible cleaning and management are built. A clean without a survey behind it is a clean done in the dark; a survey gives it the picture it needs.
The takeaway
A grease loading survey measures three connected things: how much grease has built up through the system - objectively, in microns, at points along the ducts, canopy and fan, mapping the build-up and its high spots; how well the system can be reached for cleaning - where the access panels are, whether there are enough, and whether any sections are unreachable; and how often the system needs cleaning - based on the grease level and how fast the system loads with the cooking it does. Together, these give a clear, measured picture of the system's state and what it needs.
That is why the survey is the sensible first step before cleaning or setting a schedule. It lets cleaning be done properly - targeting the worst build-ups, addressing access shortcomings, on a sensible interval - rather than in the dark, and it provides the documented basis for showing the system is being managed. So a grease loading survey is not an optional extra but the foundation: it establishes what the system is, what it needs, and how it will be kept under control. Knowing the grease level, the access and the frequency turns extraction cleaning from guesswork into something measured, targeted and evidenced.
Questions
Three connected things: the grease build-up through the system - measured objectively in microns at points along the ducts, canopy and fan; the access - how well the system can be reached for cleaning, and whether any sections are unreachable; and the cleaning frequency - how often the system needs cleaning based on the grease level and how fast it loads. Together they give a measured picture of the system's state and needs.
Objectively, with a comb gauge that reads the grease depth in microns at points along the system - the canopy, duct runs, bends, low points and fan. This produces actual figures for how thick the grease is at each point, which can be read against the recognised thresholds, rather than a subjective glance. Measuring at multiple points maps the uneven build-up and its high spots.
Because a duct is only cleanable if a cleaner can reach inside it, which depends on access panels. The survey checks where the panels are, whether there are enough, and whether the whole run can be reached - or whether sections are unreachable and would need extra panels. Access problems are common and mean sections can go uncleaned, accumulating grease and fire risk unchecked.
By measuring the current grease level and taking account of the cooking and usage. A high-output kitchen loads its ducts far faster than a light-use one, so it needs cleaning more often. The survey informs how frequently the system needs cleaning to keep the grease under the acceptable level, so the schedule fits the actual system rather than a generic assumption.
Because it gives a clear, measured picture of the system's state before any work - how much grease is there and where, whether it can be reached, and how often it needs cleaning. With that, cleaning can be done properly rather than blindly, and the survey provides the documented basis for showing the system is being managed. A clean without a survey is done in the dark.
Yes. The measured grease levels, the access assessment and the cleaning frequency it establishes are a documented picture showing the grease is being assessed and controlled - useful for a duty holder needing to demonstrate the extraction system is maintained. So the survey serves both the practical job of guiding the clean and the management job of evidencing it.
Our survey measures the grease, the access and the cleaning frequency your system needs - so the clean that follows is targeted, complete and set on a sensible interval, not done in the dark.
