Pressure Washing

A domestic pressure washer runs at two to three thousand psi. A commercial one goes far higher. At those pressures water is a cutting tool — it does not need to touch you to open you up, and it carries whatever is on the surface into the wound with it.

The injury people underestimate

A pressure washer wound looks trivial. A small slit, little bleeding, not much pain at first. Underneath, water and contamination have been driven along the tissue, and the infection risk is severe. It is treated as a high pressure injection injury — the same emergency as hydraulic fluid.

• Go to an emergency room the same day, and say those words.
• Never test the spray against your hand, your boot, or anything you are holding.
• Never point the wand at a person, including to rinse dust off them.

Using it

• Both hands on the wand, braced. A trigger pull produces real kickback, and the first pull of the day is the one that surprises people.
• Start wide and step in. Fit the widest tip that will do the job — a zero-degree tip is a cutting jet and is rarely the right choice.
• Never on a ladder. The kickback pushes you off it. Scaffold, a lift, or an extension wand from the ground.
• Watch your footing. You are making a wet, soapy, slippery surface and then standing on it, often walking backwards.
• Depressurise before changing a tip, and squeeze the trigger to bleed the line after shutting down.

Around the machine

• GFCI on any electric unit — 1926.404(b)(1)(ii) — and inspect the cord before every use. Water and temporary power is the combination that kills.
• Petrol units outdoors only. A petrol pressure washer inside a garage, a basement or a partly enclosed space is a carbon monoxide fatality, and it happens every year.
• Hot water units burn. The wand, the hose and the spray all reach scalding temperature.

PPE

Face shield over safety glasses, waterproof gloves, and boots with real tread — never open shoes. Hearing protection on the petrol units. And check what you are washing off: old paint, mould, bird droppings and chemical residue all go airborne in the spray and end up in your face.