Nozzle angle concentrates or spreads force
A narrow spray focuses energy into a small area; a wider fan distributes it. Color coding is common but not guaranteed, so identify nozzles by their marked angle and the machine manual. A zero-degree jet can cut material and should not be used for general cleaning.
Distance is a primary control
Begin with a wide nozzle and hold it farther from the surface. Move closer gradually only if needed. Test an inconspicuous area and keep the wand moving. Distance, angle, dwell time and machine output all affect whether paint, mortar, wood fibers or vehicle trim are damaged.
Detergent uses a specific low-pressure setup
Many machines draw detergent only with a soap nozzle or low-pressure setting. Use chemicals approved for the washer and surface. Never mix products unless the labels explicitly permit it, and protect plants, drains and waterways as required.
Control recoil and surroundings
High-pressure flow creates wand reaction force. Use two hands, stable footing and eye and foot protection. Do not work from a ladder; recoil can cause a fall. Keep people, pets and electrical equipment out of the spray area, and engage the trigger lock during pauses.
Safe-use checklist
- Identify the nozzle angle before connecting it.
- Start wide and far away.
- Test a hidden area.
- Never direct spray at skin, footwear or animals.
- Depressurize before changing nozzles or servicing.
- Use approved detergent and runoff controls.
Sources and further reading
- U.S. CPSC pressure-washer safety alert
- NIOSH high-pressure injection warning
- Kärcher cleaning guidance
Injection injuries can look small but are medical emergencies. Stop work, call emergency services and tell clinicians it was a high-pressure injection.