A conveying section conveys an inspected object so as to cross the X-rays irradiated from an X-ray generating section. The exhaust gas guide member forms an exhaust gas passage which introduces the exhaust gas flowing from the exhaust gas introducing portion into the intake pipe toward an opposite end of the airflow control valve relative to the valve shaft. Further, check measurements may be taken of the pool and entered into the portable computer at the pool where a comparative calculation may be made between the two sets of measurements.