If absorbed dose D = 2 Gy and w_R = 3, what is the dose equivalent H_T?

• A. 3 Sv
• B. 2 Sv
• C. 4 Sv
• D. 6 Sv

Answer: (D)

Dose equivalent combines the physical absorbed dose with a radiation-specific effect factor. You multiply the absorbed dose by the radiation weighting factor: H_T = D × w_R.

Here, D = 2 Gy and w_R = 3, so H_T = 2 × 3 = 6 Sv. The gray is a unit of energy deposited per mass, while the sievert reflects the biological impact after weighting. Since the weighting factor is 3, the biological risk associated with 2 Gy becomes 6 Sv.