Pressure Washing RAMS Guide for UK Contractors

Key Topics in a Pressure Washing RAMS

Injection injury from high-pressure jets

Water from a pressure washer operating at 1,000–3,000 psi can penetrate skin and inject water and contaminants deep into body tissue — an injury that appears minor externally but causes severe internal damage and is a medical emergency. The RAMS must specify: the minimum PPE for all operators and any persons in proximity (waterproof overtrousers and jacket, steel-toecap boots, eye protection rated for high-pressure spray, gloves rated for the pressure in use); the minimum distance rule for bystanders (typically 5 m from the spray zone); prohibition on directing the lance at any person even accidentally; and the first aid response for a suspected injection injury — treat as a serious wound and arrange immediate hospital assessment even if the wound appears trivial.

Electrical precautions

Pressure washing in industrial, commercial, and public settings involves directing high-pressure water near electrical equipment — socket outlets, light fittings, distribution boards, motors, and control panels. All electrical equipment in the spray zone must be isolated before washing begins and must not be re-energised until the area is fully dry and the isolation has been confirmed safe. The RAMS must identify every electrical installation within or adjacent to the wash area, confirm the isolation method and responsible person (AP or electrically competent person), and describe the inspection and drying procedure before reinstatement. Pressure washers must be connected via a residual current device (RCD) with a maximum 30 mA trip rating.

Surface suitability assessment

High-pressure water can damage surfaces that are not suitable for pressure washing: weakened brickwork, painted surfaces with loose adhesion, roof tiles, corrugated plastic panels, and timber boarding. Damage to a surface can create a hazard — a dislodged tile or loosened cladding panel can become a falling object hazard for people below. The RAMS must confirm that a surface suitability assessment has been carried out before works begin, that the pressure and nozzle type have been selected to match the surface (lower pressure and wider-angle fan nozzle for delicate surfaces), and that the contractor's operatives have received training in surface assessment and pressure selection.

Run-off and wastewater management

Pressure washing run-off contains suspended solids, cleaning chemicals, algae, oil, and potentially hazardous substances from the surface being cleaned. Discharge of contaminated run-off to surface water drains or watercourses without consent is a criminal offence. The RAMS must describe the run-off containment and collection method (absorbent booms around surface drains, temporary bunding, tanker collection for large volumes), the disposal route for collected wastewater (licensed waste carrier to a licensed treatment facility, or consent to discharge to the foul sewer), and the emergency spill response including the Environment Agency incident hotline. The contractor must not rely on dilution or the assumption that run-off is 'clean enough' to discharge.