Most updates to an industry standard slip past unnoticed by anyone who isn't reading BESA circulars for fun. This one shouldn't.
In March 2026, BESA published Version 2 of TR19 Air — the specification governing the internal cleanliness of general ventilation systems across the UK, distinct from its better-known sibling, TR19 Grease, which deals with kitchen extract. The headline change isn't a new cleaning method or a stricter deposit threshold. It's a brand new Section 9, and it does something the standard has never done with this much precision before: it defines what a post-clean report actually has to contain.
If you clean ducts for a living, that's not a footnote. That's the shape of your Tuesday.
What Section 9 actually asks for
Previous editions of TR19 Air were reasonably open-ended about documentation — clean it properly, prove you did, use your judgement on the detail. Section 9 closes that gap. A compliant post-clean report now has to carry a plain outcome tag for the job — full clean, partial clean, or an inspection logged as clean or not — backed by before-and-after photos shot from the same spot each time, so nobody's comparing two different angles and calling it verification. It needs deposit thickness readings taken both before and after the work, a layout showing exactly which sections got cleaned, and an honest note of which access points were used and which ones simply couldn't be reached. All of that gets tied together in a verification report carrying the job date, system type, site details, and who did the work, with layout drawings attached wherever they're relevant.
None of this is exotic. Most competent contractors were already taking before-and-after photos and noting access issues somewhere. What's changed is that "somewhere" now has a defined shape, and that shape is what insurers, EHOs, and increasingly the Ventilation Hygiene Register itself will expect to see.
The VHR angle nobody's talking about enough
The other quiet but significant change: the VHR — previously the register for grease hygiene contractors only — expanded in March 2026 to cover general ventilation too. It's worth thinking about the way BESA itself has framed it: something close to a Gas Safe register for ventilation hygiene. A client can look a contractor up, see they're independently audited, and trust the work without taking anyone's word for it.
That only works if the paperwork behind it is consistent. A register is only as credible as the reports feeding it, and TR19 Air Section 9 is effectively BESA standardising what "feeding it properly" looks like across every contractor on the list, not just the conscientious ones.
What this looks like from a ladder, not a boardroom
Here's the part that tends to get lost in standards documents: someone still has to produce this report, on site, usually while also doing the actual cleaning.
That's a technician holding a phone for photos, a gauge for deposit readings, a paper checklist or a half-remembered mental one for access points, and a pen for a signature — then trying to turn all of it into a structured, schematic-attached, properly labelled report once they're back at the depot, or more realistically, once they're home, three jobs later, trying to remember which photo belonged to which riser.
That gap, between what happened on site and what ends up in the report, is where compliance quietly erodes. Not through bad work. Through good work that never gets documented to the standard it deserves.
Where a dedicated tool actually earns its keep
This is precisely the gap Certa Vent is built around, rather than bolted onto. Every field capture — photos, deposit readings, access point notes, the outcome tag itself — is tied to the job as it happens, on site, from a phone or tablet a technician already has in their hand. The report that comes out the other end isn't assembled afterwards from memory and a camera roll; it's built to the Section 9 shape from the first photo taken.
That matters for reasons beyond convenience. A report built this way is genuinely harder to get wrong, easier for an office to check before it goes out, and far faster to produce when an insurer or an EHO asks for evidence with no notice. It also means the technician who did excellent work in a filthy riser at 7am doesn't lose the value of that work to a rushed write-up at 9pm.
The standard will keep moving
TR19 Air has been revised before and will be again — the March 2026 update also nods toward ductwork sensors and real-time contamination monitoring, clearly signalling where the next edition is heading. Contractors who treat reporting as core infrastructure, not paperwork squeezed in around the actual job, are the ones who'll absorb the next change without breaking stride.
Section 9 isn't really asking contractors to do more. It's asking them to prove, clearly and consistently, what they were probably doing already. The businesses that make that easy for their own technicians are the ones whose certificates will hold up without a second glance.