What's measured
Every LEV system should come with a document that says how well it was proven to work when it was new. Without it, no one - including the examiner - can say for certain whether the system still controls exposure. Keeping it on file is a discipline too many sites skip.
The short answer
Every LEV system should come with a document that says how well it was proven to work when it was new. Without it, no one - including the examiner - can say for certain whether the system still controls exposure. Keeping it on file is a discipline too many sites skip.
The detail
The document is the commissioning report, supported by a user manual and a log book, and it records the installed system's intended performance: hood type and position relative to the process, airflow, the static pressure behind each hood, and the face velocities. These are the figures that prove the system controlled exposure when it was signed off, and they are what every future test is measured against.
HSE is clear that this information about the installed system should be kept for the life of the equipment - a longer horizon than the test reports themselves, which must be kept for at least five years. The two are different records with different lifespans: the design and commissioning data lives as long as the system does, while each thorough examination report is retained for five years from the date it was made. Losing the commissioning data does not reset that clock, but it does leave the five-yearly reports with nothing to be measured against.
What it means for you
If the design performance data is missing, you cannot know whether the LEV is working correctly, and the examiner has to fall back on recognised guidance, standard operating data from the equipment supplier, or their own competent judgement to reconstruct a benchmark. All of those are weaker than the real commissioning figures, and they turn a clean comparison into an estimate. That is a real cost at every future test, not just the first one after the records go missing.
The document also has to keep pace with the system. If the process or the layout has changed since commissioning - a new machine, a moved hood, an added branch - the system needs recommissioning and a fresh benchmark, because the old figures no longer describe what is installed. Even a change that looks minor, like swapping a tool for a higher-output model on the same hood, can move the system outside the performance the original figures certify. Kept properly and kept current, this one document is what makes every future test a genuine comparison rather than a guess.
The service behind the guide
We test against your commissioning benchmark, and where the records are missing or out of date we help you establish and document one, with a clear report and remedial actions.
Questions
The commissioning report, supported by a user manual and a log book. It records the installed system's intended performance - hood type and position, airflow, static pressure behind each hood and face velocities.
The information about the installed LEV should be kept for the life of the equipment. That is longer than the thorough examination reports, which must be kept for at least five years.
You cannot be certain the LEV is working correctly, and the examiner must reconstruct a benchmark from recognised guidance, supplier operating data or competent judgement - all weaker than the real figures.
Yes. If the process or layout has changed since commissioning, the system needs recommissioning and a fresh benchmark, because the original figures no longer describe what is installed.
To judge whether the system is still meeting the performance it was designed for. Without a known-good baseline, the test becomes an estimate rather than a genuine comparison.
Phoenix Duct Clean · by the numbers
We test against your commissioning benchmark, and where the records are missing we help you establish and document one, with a clear report.