COSHH, law & TExT
Last year's certificate proves the system worked on one day. COSHH asks something harder: that it keeps working every day in between.
The short answer
Regulation 9 requires LEV to be maintained in an efficient state, in efficient working order, good repair and a clean condition - at all times, not once a year. A thorough examination confirms that was true on the day of the test. It cannot confirm it is still true today, because extraction systems drift the moment they go back into daily use.
The detail
Filters load and raise resistance, dampers slip, ducts develop leaks, flexible hoses tear, fan belts wear and slacken, and hoods get moved or knocked out of position. None of this announces itself. A canopy or capture hood that met its design airflow twelve months ago can be pulling appreciably less now while looking exactly the same. The certificate has not changed; the system has.
The law anticipates this, which is why the fourteen-month interval is a legal maximum rather than a target, and why HSG258 expects operator checks - at least weekly for most systems, daily for higher-risk ones - recorded in the logbook. Those checks exist precisely because control has to be held between tests, not just proven at them. A workplace that relies on last year's report and skips the in-between routine has met the letter of one date and missed the substance of the duty. Weekly checks are quick - confirming the fan runs, the airflow indicator reads correctly, the hoods and ducts are undamaged and that nothing new has been connected to the system - but they are exactly what catches drift early, while it is still cheap to fix and long before it shows up as someone's exposure.
What it means for you
Two problems follow from treating a past pass as a standing guarantee. First, the current fourteen-month window may already be open - if the last test has lapsed, there is simply no valid examination covering the system now, and a gap in evidence cannot be back-dated. Second, even inside a valid window, control that has quietly degraded is a live breach of Regulation 9 regardless of what the certificate says.
The sound position is to treat the test as one fixed point in a continuous duty. Keep the weekly checks, keep the logbook current, act on early signs of drift, and book the next examination before the window closes. That is what turns a snapshot into ongoing control - and it is the version of compliance an inspector is actually looking for.
The service behind the guide
We carry out the statutory test and help you put the weekly checks and records in place that keep performance where it should be, so compliance is continuous rather than annual.
Questions
Not automatically. COSHH Regulation 9 requires control to stay efficient at all times. A past pass proves performance on the test day only; systems drift as filters load and hoods move, so the duty continues between tests.
Filters load and raise resistance, dampers slip, ducts and hoses leak, fan belts wear, and hoods get knocked out of place. Airflow can fall well below the design figure while the system looks unchanged.
No, it is a legal maximum. Most workplaces test annually and use weekly operator checks in between, because control has to be maintained continuously, not just demonstrated at each examination.
Carry out the user checks HSG258 expects - at least weekly for most systems - record them in the logbook, act on any drop in performance, and book the next test before the current window closes.
No. If the examination window has closed there is no valid test covering the system, and the gap in evidence cannot be filled retrospectively. The exposure during the gap is itself the problem.
Phoenix Duct Clean · by the numbers
We test to Regulation 9 and help you keep the weekly checks and records that hold performance steady between visits. Call or email to set it up.