Effective Dose (EfD) is calculated as a:

Effective Dose (EfD) is calculated as a:

• A. Coulombs/kilogram
• B. Joule/kilogram
• C. Absorbed dose (D) x radiation weighting factor (Wr)
• D. Absorbed dose (D) x radiation weighting factor (Wr) x tissue weighting factor (Wt)

Answer: (D)

Effective dose reflects not just the energy deposited in tissue, but how harmful that energy is for different types of radiation and for different tissues. You start with the absorbed dose (how much energy per unit mass actually received) and adjust it with two weighting factors: Wr accounts for the biological impact of the radiation type, and Wt accounts for how sensitive the particular tissues are to radiation. Multiplying these together gives a single risk-weighted dose for the whole body, expressed in sieverts. So the correct calculation is the absorbed dose times the radiation weighting factor times the tissue weighting factor, yielding a value that represents overall stochastic risk. The other options miss either the tissue- and radiation-type adjustments or the use of those two weights together to produce a single body-wide risk measure.

Effective dose reflects not just the energy deposited in tissue, but how harmful that energy is for different types of radiation and for different tissues. You start with the absorbed dose (how much energy per unit mass actually received) and adjust it with two weighting factors: Wr accounts for the biological impact of the radiation type, and Wt accounts for how sensitive the particular tissues are to radiation. Multiplying these together gives a single risk-weighted dose for the whole body, expressed in sieverts.

So the correct calculation is the absorbed dose times the radiation weighting factor times the tissue weighting factor, yielding a value that represents overall stochastic risk. The other options miss either the tissue- and radiation-type adjustments or the use of those two weights together to produce a single body-wide risk measure.