Pressure washers put out a lot of pressure and if you put your hand in front of a pressure washer nozzle the water pressure can actually cut through the skin of your hand and cause serious wounds.
So you should never point a pressure washer nozzle at a person, animal or put your hand in front of it for any reason.
Pressure washing companies do not use their own water if there is water on site.
Most pressure washing companies will use the customers water and water spigot for their pressure washer.
However some pressure washing companies bring water with them in large water storage tanks.
The water used by the pressure washing company for residential places is not all that much or that costly.
When I hired a pressure washing company to pressure wash my driveway and house they used my water which was okay.
The water bill didn't go up by much and was only maybe $2.00 more.
Most standard pressure washers will use between 2 to 4 GPM.”
That comes a total of 120 to 240 Gallons Per Hour.
To bring that into perspective, a standard bathtub holds about 80 gallons of water.
If you were to clean your house for 1 hour straight, you'd be using the equivalent of about 2 to 3 baths.