To improve safety by detecting a human or other animal to automatically interlock an X-ray CT inspection device, and stop generation of an X-ray to stop operation, if a human being or other animal enters the prescribed area of a shield container.

An infrared-ray human body detector 8 is set at the upper position of the shield door 7 of a shield container 2 toward a proper detection area. When the sensor system of the detector 8 detects a human being or another animal in the neighborhood of the shield door 7, this is made an interlock signal, the high voltage power source of an accelerator is switched off when the accelerator is in operation, and generation of an X-ray is stopped. If the accelerator is not in operation, it is set so that its high voltage power source is not switched on, and constitution is set up in that interlocking such that the preventing of the generation of the X-ray is performed.