Power washing can be a great way to get rid of dirt from surfaces, but it also can carry harmful chemicals that could cause injury if they enter an open wound. Power-washers often use solid detergents and acids, which have been shown in studies as hazardous when coming into contact with blood.

Several dermatologists have warned their patients that they should not attempt to power-wash any areas on the body that are open due to this risk. These residential pressure washing can cause problems if the chemicals contact broken skin, but even taking a shower or using a bath could result in injury due to side effects of the cleaning agent.