In radiation protection, which metric incorporates radiation type with a weighting factor and measures dose to a specific organ?

• A. Equivalent dose
• B. Effective dose
• C. Absorbed dose
• D. Ambient dose

Answer: (A)

To understand how radiation type affects harm to a specific organ, start with the baseline idea of absorbed dose—how much energy is deposited per unit mass in that organ. But not all radiations cause the same biological effect, so we multiply that energy deposition by a radiation weighting factor that reflects the type of radiation. The result is the equivalent dose for that organ, expressed in sieverts, and it captures both the dose actually delivered and the differing biological impact of the radiation type for that specific organ. This is the metric that links the physical dose to potential harm for a particular organ. If you were looking to estimate risk for the whole body, you’d combine organ doses with tissue weighting factors to get the effective dose, but for a single organ the equivalent dose is the right concept. Absorbed dose alone doesn’t account for radiation type, and ambient dose describes environmental exposure rather than dose to a specific organ.