Home / Kitchen Extraction Cleaning / Guide
Kitchen extraction - the survey
The certificate at the end of an extract clean is only as good as the clean behind it - and the clean is only as complete as the survey that scoped it. A detailed survey up front finds the whole system, so the clean covers all of it and the certificate genuinely means what it says. Skip the survey, and the certificate can cover less than it appears.
The short answer
A detailed survey before an extract clean maps the whole system - its full run, its access points and where access is lacking, and where the worst grease sits - so the clean can be scoped to cover all of it. That matters to the certificate, because a certificate only genuinely verifies what was actually cleaned and checked: if the survey missed part of the system, the clean and the certificate cover less than they appear to. A thorough survey is what lets the certificate honestly certify the whole system, not just the parts that happened to be found.
The survey sets the scope
A detailed survey before an extract clean does an essential job: it determines what the clean will actually cover. The survey maps the system - tracing the full run of ductwork, identifying its extent and configuration, finding the access points and where access is lacking, and locating where the grease is heaviest. That map is what the clean is scoped against, so what the survey finds is, in effect, what the clean covers. The survey defines the job.
This makes the survey the foundation of the whole clean, because a clean can only address what was identified to be cleaned. If the survey is thorough and finds the whole system, the clean can be scoped to cover all of it; if the survey is cursory and misses part of the system - a length of duct, a section without access, an area of heavy grease - then that part is likely to be left out of the scope and go uncleaned. The completeness of the survey therefore sets the completeness of the clean, which is why a detailed survey matters before any thorough extract clean.
What a detailed survey finds
A detailed survey finds the things that determine whether a clean is complete. It traces the whole run of the ductwork, so the full extent of the system to be cleaned is known - not just the obvious parts near the canopy and fan, but the entire run through the building. It identifies the access situation - where there are access panels and where there are not - so it is known upfront where access will need to be created to reach and clean the whole system. And it locates where the grease is heaviest, so the clean can target the areas of greatest build-up and fire risk.
These findings shape a complete, properly-scoped clean. Knowing the whole run means the clean can cover all of it; knowing where access is lacking means the access to reach the whole system can be planned and provided; knowing where the grease is worst means the effort is directed where it is most needed. A cursory survey that finds only the accessible, obvious parts leads to a clean that covers only those - missing the sealed sections, the inaccessible runs, the hidden heavy grease. The detail of the survey is what makes the difference between a clean that addresses the whole system and one that addresses only part of it.
Why it matters to the certificate
Here is why the survey matters to the certificate specifically: a certificate only genuinely verifies what was actually cleaned and checked. A TR19 verification certifies that the system - as cleaned and measured - meets the standard, based on the cleaning and the verification carried out. But if part of the system was never in scope because the survey missed it, then that part was not cleaned, not measured, and not covered by the certificate - even though the certificate might appear to certify the system. The certificate can only cover what the clean covered, which the survey determined.
So a certificate resting on a cursory survey can cover less than it appears to. If the survey missed a length of duct, that duct is uncleaned and unverified, but the certificate for the clean that was done might give the impression the system is compliant - when a whole section was never addressed. That is a serious gap: an apparently-clean certificate over a partly-uncleaned system, with the uncovered part still holding grease and fire risk. The certificate's honesty depends on the clean covering the whole system, which depends on the survey finding it. A detailed survey is what lets the certificate genuinely mean the whole system is clean.
The survey underpins the certificate's value
So the survey, the clean and the certificate form a chain, and the survey is the first link that the others depend on. A detailed survey finds the whole system; the clean, scoped against it, covers the whole system; and the certificate then honestly verifies the whole system, because the whole system was actually cleaned and checked. The certificate's value - its ability to genuinely demonstrate the system is compliant - rests on the clean being complete, which rests on the survey being thorough.
This is why skipping or skimping the survey undermines the certificate even if the certificate itself looks proper. A verification certificate can be a genuine TR19 report - photographs, measurements, the lot - and still cover less than the whole system, if the survey scoped the clean too narrowly. The verification is honest about what was cleaned, but what was cleaned was incomplete. So the detailed survey is not a preliminary to be rushed but the foundation of a certificate that genuinely covers your whole system. The certificate can only be as complete as the clean, and the clean only as complete as the survey.
The takeaway
A detailed survey before an extract clean maps the whole system - its full run, its access and where it is lacking, and where the worst grease sits - so the clean can be scoped to cover all of it. That matters to the certificate because a certificate only genuinely verifies what was actually cleaned and checked: if the survey missed part of the system, the clean and the certificate cover less than they appear to.
So the survey, the clean and the certificate are a chain, and the survey is the link the others depend on. A thorough survey lets the clean cover the whole system and the certificate honestly certify it; a cursory one leads to a clean that covers only part, and a certificate that can appear to cover the system while a whole section was never addressed. The certificate is only as complete as the clean, and the clean only as complete as the survey - which is why a detailed survey is what makes the certificate genuinely mean your whole system is clean.
Questions
Because the survey determines what the clean will cover - it maps the system's full run, access and worst grease, and the clean is scoped against that map. What the survey finds is, in effect, what the clean covers, so a thorough survey is the foundation of a complete clean.
The whole run of the ductwork (so the full extent is known), the access situation (where panels exist and where access must be created), and where the grease is heaviest (so the clean targets the greatest build-up and fire risk). These findings shape a complete, properly-scoped clean.
A certificate only genuinely verifies what was actually cleaned and checked. If the survey missed part of the system, that part was not cleaned, measured or covered - even though the certificate might appear to certify the system. The certificate can only cover what the clean covered.
Yes - if it rests on a cursory survey. A missed length of duct is uncleaned and unverified, but the certificate for the clean that was done might give the impression the system is compliant, when a whole section holding grease and fire risk was never addressed.
Yes. A verification certificate can be a proper TR19 report - photographs, measurements and all - and still cover less than the whole system if the survey scoped the clean too narrowly. The verification is honest about what was cleaned, but what was cleaned was incomplete.
A detailed survey that finds the whole system, so the clean covers all of it and the certificate honestly verifies it. The certificate is only as complete as the clean, and the clean only as complete as the survey - which is why the survey underpins the certificate's value.
We survey the whole extract system in detail before cleaning - mapping the full run, access and worst grease - so the clean covers everything and the certificate genuinely certifies it all.
