Every substance, its hazard and its control
The substances on site, their hazard class, controls, PPE and disposal, linked to the task sequence and the competency matrix. Ten substances are indexed for the coating works; six are high-hazard and four trigger mandatory health surveillance. The isocyanate top coat is the one that sets the tightest controls on the job.
- Client
- Caldicot Viaduct Coatings
- Site
- M48 over Severn corridor · NP26
- Work type
- Bridge coatings, strip, prime, build, finish
- Reference
- BAI-COSHH-CDV-COAT-001
- Sector
- Infrastructure
- Status
- For approval
Illustrative example: fictional project and parties.
Four exposures under health surveillance
The coating works cover 1,800 m² over a 12-week programme behind a containment scaffold. The index is generated from the materials specification against a substance hazard library, with a manufacturer safety data sheet attached to the project record for each item. Four exposures trigger pre-employment, periodic and post-employment health surveillance: isocyanate from the polyurethane top coat, lead from existing coatings disturbed during abrasive blasting, solvents during sustained spray campaigns, and skin and respiratory sensitisers.
The polyurethane top coat contains isocyanates, a reportable disease under RIDDOR if occupational asthma develops. Air-fed positive-pressure RPE is mandatory during spray; FFP3 cartridge RPE alone is not acceptable. No operative applies it without prior occupational-health clearance and recorded training, and the spray-bay segregation envelope stays clear of all other operatives.
The substance register
A sample of the indexed substances with their headline hazard class and the controlling measure. Training and health-surveillance status is recorded against each in the full index.
| Ref | Substance | Hazard class | Controlling measure |
|---|---|---|---|
| S01 | Zinc-rich epoxy primer | Flammable, skin sensitiser, STOT-RE | Air-fed RPE, spray booth, LEV, isolate zone |
| S03 | Polyurethane top coat, aliphatic | Flammable, respiratory sensitiser (isocyanate) | Air-fed RPE only, segregate, OH clearance |
| S04 | Polyamine activator or hardener | Skin corrosion, eye damage, sensitiser | Decant under LEV, splash goggles, eye-wash within 10m |
| S05 | Surface preparation acid wash | Skin corrosion, eye damage | Acid-resistant gloves, goggles, hand application only |
| S06 | Solvent cleaner, aromatic (xylene) | Flammable, aspiration toxicity | Dedicated cleaning bay, LEV, earthed container |
| S10 | Garnet abrasive blasting media | Respiratory dust, high-velocity injury | Sealed enclosure, air-fed helmet, specialist operative |
Controls, disposal and approval
Storage is segregated and bunded, with flammables in a solvent cabinet and quantities capped on the bridge deck. Empty containers and off-spec material route to a licensed hazardous-waste hauler; used solvent and spent blast media never reach a drain or surface water, and spent media is assessed for lead contamination from the existing coatings before disposal.
Final approval sits with the competent occupational-health adviser before mobilisation. Pre-employment, periodic and post-employment surveillance is put in place for the substances at required status, and no operative works on those exposures without recorded clearance.
Health surveillance and the controls it rests on
Four exposures trigger surveillance. Each has a defined type and interval, and no operative works the exposure without recorded clearance in date.
| Exposure | Surveillance | Interval |
|---|---|---|
| Isocyanate, polyurethane top coat | Lung function and respiratory questionnaire | Pre-employment, then periodic |
| Lead, disturbed existing coatings | Blood-lead monitoring | Pre-employment, then periodic |
| Solvents, sustained spray campaigns | Skin and respiratory check | Periodic through the campaign |
| Sensitisers, skin and respiratory | Skin inspection and questionnaire | Pre-employment and on symptoms |
| Hazard route | Primary control on this job |
|---|---|
| Respiratory | Air-fed positive-pressure RPE for spray, LEV at decant, segregated spray bay |
| Skin and eye | Chemical-resistant gloves, splash goggles, eye-wash within 10m of decant |
| Fire | Solvent cabinet, earthed containers, deck quantities capped to the working day |
| Environmental | Bunded storage, licensed hazardous-waste hauler, no discharge to drains or river |
Surveillance is run by the appointed occupational-health provider and the results are confidential to the individual. Health records for the lead and isocyanate exposures are retained for 40 years as required, and a flagged result routes to the adviser before that operative returns to the exposure.