What is the difference between operating and working pressure?

The operating pressure (also shut-off pressure) is the maximum achievable water pressure when no water is flowing out of the nozzle. In practice, the work pressure is relevant. This pressure is actually available during cleaning. When comparing brands and models, it is important to note whether the pressure refers to the operating pressure or the actual working pressure. This is the best way to compare. As a rule of thumb it can be said that the working pressure is about 10% below the operating pressure.