Spray Booth Operation SWMS

Spray booth operation is the primary engineering control for managing isocyanate, solvent vapour, and overspray exposure in auto body workshops. A booth that fails to maintain adequate airflow velocity exposes painters to chemical concentrations that exceed workplace exposure limits within minutes of commencing a spray cycle. The WEL for isocyanates drops by 75 per cent to 0.005 mg/m3 from 1 December 2026, making booth performance critical. This template covers pre-spray checks, operation procedures, and post-spray purge cycles mapped to AS/NZS 4114 and the binding Spray Painting and Powder Coating Code of Practice effective 1 July 2026.

Legal Requirements

regulation

WHS Regulation 2025 Part 7.1 — Hazardous Chemicals; AS/NZS 4114 Spray Painting Booths

hrcw category

Work in a contaminated or flammable atmosphere

code of practice

Spray Painting and Powder Coating (binding 1 July 2026 under Section 26A)

section 26a binding

Yes — Spray Painting and Powder Coating code binding July 2026. Non-compliance is admissible as evidence of breach.

Hazards

Hazard	Consequence	Likelihood
Isocyanate vapour and aerosol accumulation from inadequate booth airflow	Occupational asthma (irreversible), respiratory sensitisation	Likely
Solvent vapour ignition from electrostatic discharge or faulty electrics	Fire, explosion, severe burns, fatality	Unlikely
Overspray particulate inhalation from blocked or saturated filters	Respiratory irritation, paint pigment accumulation in lungs	Possible
Oxygen depletion in booth during extended spray cycles	Dizziness, loss of consciousness, asphyxiation	Unlikely
Skin contact with isocyanate-containing overspray mist	Skin sensitisation, contact dermatitis	Likely

Controls (Hierarchy of Controls)

Verify booth airflow velocity meets AS/NZS 4114 minimum of 0.5 m/s before every spray cycle using calibrated anemometer

Replace intake and exhaust filters at manufacturer-specified intervals and whenever pressure differential exceeds limit

Ensure all electrical fittings within the booth are intrinsically safe and explosion-proof rated

Require supplied-air respiratory protection for all two-pack paint application inside the booth

Maintain booth negative pressure relative to workshop to prevent overspray migration

Run post-spray purge cycle for minimum time specified by booth manufacturer before removing RPE

Conduct six-monthly booth performance testing by qualified technician with documented results

Recent Prosecutions

SafeWork NSW v Auto Body Workshop (Sydney)$180,000

Workshop operated spray booth with airflow below AS/NZS 4114 minimum and failed to provide supplied-air RPE to painter applying two-pack paint. Worker developed occupational asthma.

2023 — SafeWork NSW Prosecution Database

What Your SWMS Must Include

✓Pre-spray airflow verification procedure with minimum acceptable velocity recorded

✓Filter replacement schedule and pressure differential monitoring protocol

✓RPE selection, fit testing, and maintenance requirements for each paint type

✓Emergency shutdown and evacuation procedure for booth fire or extraction failure

✓Post-spray purge cycle duration and RPE removal criteria

Need a compliant Spray Booth SWMS?

Our WHS consultants develop spray booth SWMS with airflow monitoring protocols mapped to AS/NZS 4114 and the incoming WEL values.