What are the SI units for exposure, dose, and dose equivalent?

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Multiple Choice

What are the SI units for exposure, dose, and dose equivalent?

Understanding the units used for exposure, absorbed dose, and dose equivalent helps connect what we measure to how the body is affected. Exposure measures how much ionization an air volume experiences, and its SI unit is coulombs per kilogram (C/kg). Absorbed dose tells us how much energy from the radiation is deposited in a kilogram of matter, so the SI unit is the gray (Gy), where 1 Gy equals 1 joule per kilogram. Dose equivalent adapts that energy deposition to the biological effect, using weighting factors that reflect different radiations; its SI unit is the sievert (Sv), with 1 Sv equal to 1 Gy multiplied by the radiation weighting factor (for X-rays and gamma rays the factor is 1, so numerically 1 Gy = 1 Sv in those cases). Historically, you may see roentgen, rad, and rem, but these are non-SI units. So the SI set for exposure, dose, and dose equivalent is coulombs per kilogram, gray, and sievert.

Understanding the units used for exposure, absorbed dose, and dose equivalent helps connect what we measure to how the body is affected. Exposure measures how much ionization an air volume experiences, and its SI unit is coulombs per kilogram (C/kg). Absorbed dose tells us how much energy from the radiation is deposited in a kilogram of matter, so the SI unit is the gray (Gy), where 1 Gy equals 1 joule per kilogram. Dose equivalent adapts that energy deposition to the biological effect, using weighting factors that reflect different radiations; its SI unit is the sievert (Sv), with 1 Sv equal to 1 Gy multiplied by the radiation weighting factor (for X-rays and gamma rays the factor is 1, so numerically 1 Gy = 1 Sv in those cases).

Historically, you may see roentgen, rad, and rem, but these are non-SI units. So the SI set for exposure, dose, and dose equivalent is coulombs per kilogram, gray, and sievert.

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