What principle do personnel radiation monitoring devices operate on?

Personnel radiation monitoring devices operate on the principle that they can measure exposure to ionizing radiation through various mechanisms. The correct choice indicates that these devices can utilize ionization, luminescence, and thermoluminescence as different methods to detect radiation.

Ionization refers to the process where radiation interacts with atoms, knocking out electrons and creating charged particles. This principle is foundational in devices such as ionization chambers and Geiger-Müller counters, which measure ion pairs created by radiation.

Luminescence includes methods that involve light emission when certain materials are excited by radiation. This can be seen in devices designed to emit light when exposed to radiation, which is then measured to quantify exposure.

Thermoluminescence specifically involves materials that store energy from ionizing radiation. When these materials are heated, they release this energy as light, which can then be quantified to determine the amount of radiation exposure. Thermoluminescent dosimeters (TLDs) are common examples of this type of device.

Thus, by encompassing all three principles—ionization, luminescence, and thermoluminescence—personnel radiation monitoring devices take advantage of different characteristics of materials to provide comprehensive radiation dose assessments.