Blasting years of grime off your deck, patio or siding with a high-powered pressure washer can feel pretty satisfying — but less so if you land in the ER as a result.

Pressure washers, aka power washers, lead to thousands of injuries each year. More than 6,000 people wind up in hospital emergency rooms with lacerations, punctures and even eye damage from accidentally spraying themselves, according to a recent Consumer Reports report.

Most injuries invovle cuts. These may seem minor at first, but their benign appearance may cause people to delay treatment, resulting in infection and even amputation, according to the Centers for Disease Control and Prevention (CDC). People also sustain injuries caused by objects and debris sent airborne by the spray.

Residential power washers, which come in gas and electric (generally less powerful) models, shoot concentrated water at very high pressure, usually ranging from 1,000 psi (pounds per square inch) to 3,000 psi or more. At lower psi, the machines are ideal for simple home projects like washing a car or cleaning dirt and debris off siding. Most home projects require a range of 1,300 to 2,400 psi according to the DIY website FamilyHandyMan.com, Higher pressures may be needed for more challenging projects, like removing stains from decks and concrete walkways.

Greater water pressure brings greater injury risk.

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Experts advise following the basic safety guidelines when using a pressure washer.

1. Keep the washer well maintained. If you live in a colder climate or won’t be using the machine for several months, drain water and gas from the system. Otherwise, follow the manufacturer’s maintenance recommendations in your instruction manual.

2. Read those directions. Know how your power washer and its safety devices work and what to do in case something goes wrong. Always operate within the safety guidelines the manufacturer recommends.

3. Wear protection. That means safety googles, gloves and boots or other leather footwear.

4. Start with a lower setting. Start with a low-pressure setting to prevent recoil and kickback — especially if you're using a ladder. The force of the spray can propel you backward off the ladder. The same applies if you're using a lance extension to extend the spray wand, which can kick back and potentially strike nearby electrical lines. Use a nozzle with a wider pattern first and reduce the psi so you don’t inadvertently blast off siding instead of clean it. Keep the nozzle moving rather than focused on one spot.

5. Avoid zero-degree nozzles. In February, Consumer Reports announced they no longer recommend pressure washers with zero-degree settings, which provide a very narrow stream. These streams are capable of causing more serious injury. Consumer Reports recommends using nozzles with a 15-degree or greater range. (The Pressure Washer Manufacturers’ Association reportedly stands by the more concentrated nozzle, saying they aren’t hazardous if used according to instructions).

6. Watch where you spray. Avoid blasting the stream upwards at a steep angle under house siding. Also, don’t point the spray directly onto glass window panes, corners, under widow edges or doors or into your dryer or attic vents.

7. Don't put your hand in front of the nozzle. This should be a no-brainer. The pressured water can cut you.

8. Keep water and electricity apart. Avoid spraying near electrical outlets, outdoor lighting fixtures and power lines, says John Drengenberg, consumer safety director for UL. If using an electrical pressure washer, connect it to an outlet with a ground fault circuit interrupter (GFCI) to avoid the risk of electrocution.

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9. Work in open areas. Never use a gas-powered model indoors. Stay in a well-ventilated area to reduce carbon monoxide exposure, the CDC advises.

10. Never use a pressure washer around children or pets. And never leave a running machine unattended as children may injure themselves thinking it’s a garden hose.

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Ronald Agrella is a freelance writer and former editor of The Boston Globe’s Boston.com.