Pressure washers can be dangerous

A garden hose, soap and elbow grease can take care of many a cleanup job – if you want to spend all day on it. But if you have better things to do, a pressure washer speeds up all sorts of onerous tasks, from scrubbing grime and mildew from siding to getting oil stains off a driveway to washing a car.

Pressure washers use either a gas engine or an electric motor, a pump and a concentrating nozzle to boost water pressure from your hose connection by 30 to 80 times, explains Consumer Reports. Though a garden hose alone delivers water pressure at about 50 pounds per square inch (psi), pressure washers can generate 1,500 to 4,000 psi. That’s a lot of power. And when operated properly, they blast away stains without damaging the surface material beneath.

But despite the benefits, they can cause serious injury, Consumer Reports notes – and few consumers may appreciate just how serious. A pressure washer’s powerful spray is hazardous when misdirected, strong enough to damage skin in an instant. Lacerations are the most-common injury, followed by bruises, punctures and eye injuries.

“The extreme danger with pressure washers is that even with what seems a very minimal skin break, the fluid can get deep into the tissue and spread out and cause bacterial infection,” says Dr. Howard Mell, a spokesman for the American College of Emergency Physicians. He recalls a patient who was hit in the calf, producing a laceration less than 2 inches across. But internally, there was infection to the muscle. It took a long operation and months of physical therapy for the patient to heal.

Pressure washers are sold with either a set of interchangeable nozzles or an adjustable wand tip, both of which usually allow users to vary the flow of water from zero degrees, the finest, to about 65 degrees, depending on the task. They’re inherently dangerous no matter which spray tip or setting you’re using. But the unnecessary risk of using a zero-degree nozzle – which concentrates the tool’s full pressure into a single, pinpoint blast – outweighs the utility because the spray can cause severe damage in a short amount of time. And higher-degree nozzles can get the job done.

The Pressure Washer Manufacturers’ Association notes that a pressure washer’s manual and markings on the products themselves describe safe use, and it stands by the utility of zero-degree nozzles.

“The zero-degree nozzle in this case may be used to extend the reach of the water and thus eliminate the need of a ladder,” the trade group said in a statement. “In addition, it may also be used for etching or removing extremely stubborn debris prior to washing or rinsing using 15-degree or larger-angle nozzles.”

An estimated 6,057 people in 2014 went to an emergency room with injuries related to pressure washer use, according to the Consumer Product Safety Commission. And 14 percent of those ER visits led to additional hospitalization. (Not all of the injuries could be attributed to contact with a powerful spray.)

The same kind of cleaning can be done with wider-angle settings; it just might take a bit longer. And many pressure washers let you connect wand extensions to reach higher surfaces without resorting to a zero-degree nozzle.

Based on the potential extreme risk of very narrow nozzles and their limited benefit, Consumer Reports no longer recommends pressure washers that come with nozzles that produce sprays of less than 15 degrees, despite how well they clean.

To learn more, visit ConsumerReports.org.

2016 Consumers Union Inc.