Read: 3 mins. Pressure washers are a fast, convenient way to remove gunk, but they can also be VERY dangerous if used improperly. They work by taking in low-pressure water, turn it into a super high-powered stream (with a gas or electric motor), then through a nozzle where it can be so strong, it can actually damage wood/stone and inflict serious harm to people and animals. So, how do you use them? This article covers the Do's and Do Not's, and what they are commonly used for.