Benzoyl chloride is a new WEL listing with an 8-hour TWA of 2.8 mg/m³ (0.5 ppm). Until 30 November 2026, WES remains the reference; from 1 December WEL applies once implemented. Check the WHS regulator.
Measure and define SEGs
This reactive acyl chloride is typically vapour, with aerosol possible during spraying, transfer or containment failures. State analyte, mg/m³/ppm basis, 8-hour TWA and whether task samples are time-weighted or reported as peaks. Do not invent a STEL.
- Drum/IBC charging and vapour return.
- Process sampling near open vapour paths.
- Filter change and maintenance line-break.
- Kilo-lab, pilot, spills, waste and contractors.
Build SEGs from tasks: charge operators, sampling technicians, filter crew, maintenance and lab. Log temperature, purge, LEV, location and RPE as context.
Sampling strategy
- Full-shift personal samples on representative campaigns plus task samples for open transfer.
- Agree sorbent/media stability and recovery with the lab before mobilisation.
- Document flow, breakthrough, blanks, humidity and co-contaminants.
- Sample enough batches to show variability; static samples only diagnose LEV.
Controls and interpretation
Use closed charging, vapour return, sealed sampling, LEV and purge-before-break before RPE. Plan against 2.8 mg/m³ (0.5 ppm), report LOD/LOQ and assumptions, and use task peaks for control diagnosis without inventing a STEL. Address dermal risk separately. Contact Occ Hygiene.
