Which of the following methods is NOT one of the three basic methods of radiation protection?

• A. Time
• B. Distance
• C. Shielding
• D. Calibration

Answer: (D)

The correct choice of "D" refers to calibration not being one of the three basic methods of radiation protection, which are time, distance, and shielding.

Time, as a method of radiation protection, indicates that minimizing the duration of exposure to radiation reduces the total dose received. This principle is grounded in the understanding that the less time one spends near a radiation source, the lower the potential dose of exposure.

Distance involves maximizing the distance from the radiation source to decrease exposure. Radiation intensity diminishes with increased distance due to the inverse square law, meaning that even small increases in distance can significantly reduce radiation levels.

Shielding is an essential method involving the use of barriers made from materials that can absorb or deflect radiation, protecting individuals by reducing the intensity of radiation that reaches them.

Calibration, while important in the context of ensuring that radiation detection equipment is properly measuring radiation levels, does not serve as a method for protecting individuals from exposure to radiation. Instead, it is a quality assurance process that verifies the accuracy and functionality of protective measures rather than being a protective method itself.