Which of the following is NOT a method to determine the amount of radiation exposure?

The amount of radiation exposure can be measured by several factors that directly influence it, one of which is the type of radiation. The other options listed are key variables in determining a person's radiation exposure.

Time exposed to the source is crucial because the longer a person is exposed, the greater the potential for radiation dose accumulation. Shielding from the source is also significant; different materials can block different types of radiation, thereby reducing the dose received. Distance from the source is another critical factor; the farther one is from the radiation source, the lower the exposure due to the inverse square law, which states that radiation intensity decreases with the square of the distance from the source.

In contrast, while the type of radiation can affect the biological impact and effectiveness of shielding, it does not directly measure the amount of radiation exposure in terms of dose received. Instead, it influences how exposure should be managed and mitigated. Therefore, it does not serve as a method to quantify exposure levels but rather as a consideration for safety protocols.