Phoenix Journal · Ductwork
Every duct cleaning quote carries a cluster of accreditation logos, and most of us treat them as decoration. Here is what the bodies behind them actually govern - and where it shows up at sign-off, at audit, and at claim.
Compliance & competence
Almost every quote you receive for kitchen extract or duct cleaning will carry a cluster of logos - and it is easy to treat them as decoration rather than proof of anything real.
The trade is full of acronyms, and a fair few of them are worn loosely. A firm can print “TR19 compliant” on a leaflet without holding a single relevant qualification, because the phrase itself is not policed. What is policed - and what genuinely changes the paperwork you can rely on - is membership of the schemes that sit behind those words. So it is worth understanding which accreditation bodies actually govern this work, what they check, and where the difference shows up when it matters: at sign-off, at audit, and at the moment an insurer asks to see your records.
This is not about collecting the most stickers. It is about knowing which ones carry weight, and why a certificate issued by an accredited contractor is a fundamentally different document from one typed up by a firm with a pressure washer and good intentions.
Four names do most of the work here, and it helps to keep them apart rather than lumping them into one vague idea of “being certified”.
BESA - the Building Engineering Services Association - is the trade body that writes and publishes the standards. Its guide TR19 Grease is the reference document that insurers, fire risk assessors and building engineers use to judge whether a kitchen extraction system is being maintained properly. BESA also owns the training: the Grease Hygiene Operative (GHO) qualification for the person doing the physical clean, and the Grease Hygiene Technician (GHT) qualification for the person allowed to inspect, verify and sign the certificate. TR19 Grease sets these as minimum competency levels rather than nice-to-haves.
BESCA - Building Engineering Services Competent Assessment - is the certification arm. It runs the Vent Hygiene Register (VHR) and the higher Vent Hygiene Elite (VHE) scheme, which independently audit member firms and hold a database of their post-clean reports. Since the standard was revised, only companies on that register - with qualified technicians on the books - can properly issue TR19 Grease certification. VHE in particular is recognised by the insurance-backed RISCAuthority and by the Fire Protection Association, which recommends that kitchen extract cleaning be carried out by contractors holding either BESCA Vent Hygiene Elite or LPCB LPS 2084 certification.
BOHS - the British Occupational Hygiene Society - governs the parallel world of local exhaust ventilation. Its P601 qualification (a Level 4 award, taught over four days) is the recognised benchmark for the person carrying out the thorough examination and testing of an LEV system, with P604 sitting above it for commissioning and complex diagnostic work.
UKAS - the United Kingdom Accreditation Service - sits above all of it as the national accreditation body. It does not clean ducts or test extraction; it accredits the organisations and laboratories that do, which is why a UKAS-accredited testing house carries more evidential weight than an individual certificate alone.
The honest answer to “does accreditation change the actual cleaning?” is: not the physical scrubbing, particularly. A skilled uncertified operative can get a duct visibly clean. The difference is in everything that surrounds the clean - the evidence, the sign-off, and the accountability - and that is precisely the part you are paying for.
The first difference is who is allowed to say the job passed. Under TR19 Grease, a valid certificate cannot be issued by just anyone who turned up. It has to be signed off against verified measurements by someone holding the GHT qualification, working for a firm on the BESCA register. The verification is not a glance and a thumbs-up: it uses defined methods - a Wet Film Thickness Test for soft grease deposits and a Deposit Thickness Test for hard carbonised ones - with matched before-and-after readings and photographs at fixed access points. Cleaning is required once mean grease depth reaches 200 microns, and a proper post-clean report demonstrates it has been brought below 50 microns. That is a measurable, contestable claim rather than an opinion.
The second difference is the audit trail. An accredited firm does not just hand you a certificate; its reports are lodged with the scheme, and the scheme audits members’ work to check standards are being held. So the paperwork behind an accredited clean is independently backed rather than self-declared. If you ever need to defend your maintenance record - to a fire officer, to a landlord, to a loss adjuster - there is a third party standing behind the document, not just the contractor who was paid to produce it.
The third difference is what happens when there is a claim. Most commercial property and food-business insurance policies now require extraction to be maintained in line with TR19. After a fire, the insurer asks for your TR19 certificates. If they are missing, or show cleaning was overdue, or were issued by a firm with no standing to issue them, the claim can be challenged even where the fire had nothing to do with the ductwork. An accredited certificate is, in that moment, the difference between a record that holds and a record that unravels.
The same logic runs through LEV. The law - COSHH Regulation 9 - does not name a qualification; it requires a “competent person” to thoroughly examine and test the system at least every fourteen months. HSE, UKAS and international bodies recognise the BOHS P-series as the benchmark for that competence, but they are careful to call them benchmarks, not statutory tickets. A certificate on its own is not competence. Sample reports on comparable systems, and accreditation of the organisation behind the examiner, are the stronger signals - and a thorough LEV examination looks at the whole airflow picture, including whether make-up air is adequate rather than only measuring at the hood.
Once you know which bodies matter, checking a firm becomes quick. The trick is to look past the wording on the website and ask for the things that cannot be faked.
None of this makes accreditation a formality to tick off. It is the mechanism that turns a clean you cannot see - hidden inside ductwork you will never inspect yourself - into a documented, defensible position. The value is not the logo; it is the fact that an independent body has agreed to stand behind the claim the logo represents. That is worth paying for, and it is worth checking. Keeping accredited work on a planned schedule, rather than reacting once deposits build up, is also what keeps you continuously inside the standard - which is where planned preventive maintenance earns its place.
Questions
TR19 Grease is the standard, and the phrase “TR19 compliant” is not itself policed, so anyone can print it. What carries weight is a certificate issued by a firm on the BESCA Vent Hygiene Register or Vent Hygiene Elite scheme, signed off by a technician holding the BESA GHT qualification against verified measurements. A certificate from a firm with no such standing may not hold up when an insurer or fire officer examines it closely.
BESA, the Building Engineering Services Association, writes and publishes the standards such as TR19 Grease and owns the GHO and GHT training qualifications. BESCA, Building Engineering Services Competent Assessment, is the certification body that audits contractors and runs the Vent Hygiene Register and Vent Hygiene Elite schemes. In short, BESA sets the rules and BESCA checks that firms are following them.
No. COSHH Regulation 9 requires a “competent person” to thoroughly examine and test local exhaust ventilation at least every fourteen months, but it does not name a specific qualification. The BOHS P601 award is the recognised benchmark for that competence, endorsed by HSE and UKAS, but it is a benchmark rather than a statutory ticket. Sample reports on similar systems and accreditation of the examiner's organisation are equally strong signals to look for.
Phoenix Duct Clean · by the numbers
Phoenix surveys and cleans kitchen and building ductwork to the TR19 standard - measured, cleaned and certificated, UK-wide.