Time, distance, and shielding are used to manage exposure hazards from which source?

• A. Chemical
• B. Biological
• C. Radiation
• D. Thermal

Answer: (C)

Time, distance, and shielding are the primary means of reducing exposure to ionizing radiation. Limiting the time you spend near a radioactive source lowers the total dose you accumulate. Increasing the distance from the source dramatically decreases exposure due to the inverse-square relationship—that is, doubling the distance reduces the dose to a quarter. Shielding provides a barrier between you and the source, with the shielding material chosen based on the type of radiation to absorb or block it.

These controls specifically address radiation hazards, not chemical, biological, or thermal hazards, which are managed through different protective strategies.