Units of Measure for Radiation cont'd

DOE-HDBK-1130-98

Module 1: Radiological Fundamentals

Instructor's Notes

b. Is defined for any material.

c. Applies to all types of radiation.

d. Does not take into account the potential effect that different

types of radiation have on the body.

e. 1 rad = 1000 millirad (mrad).

3. Rem (Roentgen equivalent man)

a. A unit for measuring dose equivalence.

b. Is the most commonly used unit.

c. Pertains to the human body.

d. Takes into account the energy absorbed (dose) and the

biological effect on the body due to the different types of

radiation.

The Quality Factor (QF) is used as a multiplier to reflect the

relative amount of biological damage caused by the same

amount of energy deposited in cells by the different types of

ionizing radiation. Rem = rad x QF.

Quality Factors:

alpha

= 20

beta

gamma/x-ray

= 2-11(depending on the energy)

e. 1 rem = 1,000 millirem (mrem).

EO8 Convert rem to

millirem and millirem to

rem.

4. Radiation dose and dose rate

a. Radiation dose rate is the dose per time.

b. Example:

1) Radiation dose rate = dose/time.

2) Radiation dose equivalent rate = mrem/hr.