Abstract: In order to explain the security of high explosives (HEs) when measuring their properties with X- or γ-rays and increase the testing speed, the threshold of the rays' intensity was achieved by limiting the interaction probability between the high explosives' molecules and the photons, the absorption ratio of the photons' energy into the high explosives based on the mathematical norm commonly used in engineering. The security of the high explosives was validated with ordinary radioactive detection equipment, and research results show that the high explosives would be safely measured until the imposed radioactive intensity was raised to 10⁴ W/m² in order of magnitude.