In the process of using the X-ray machine, why do we use a special handbrake switch?

In the process of using the X-ray machine, why do we use a special handbrake switch?
When talking about why to use the handbrake switch, we must first know the imaging principle of the X-ray machine. In short, the imaging of the X-ray machine uses the penetration properties of X-rays, as well as the density and thickness of the object to be photographed. difference.
In addition, we must also know that X-rays contain ionizing radiation, and when the ionizing radiation reaches a certain dose, it will cause radiation damage to the human body. At the same time, when X-rays are generated, a lot of electricity is consumed and a lot of heat is generated.
Therefore, in the process of using the X-ray machine, the X-ray machine cannot be kept on all the time, and the start-up time will be very short, so we cannot use the general switch, but should choose a special handbrake switch.