Primary radiation

DOE-HDBK-1109-97

Radiological Safety Training for Radiation-Producing (X-Ray) Devices

Instructor's Guide

Primary radiation: Radiation coming directly from the target of the X-ray tube or from the sealed

source.

Quality factor: An energy-dependent dimensionless factor by which absorbed dose is to be multiplied to

obtain, on a common scale for all ionizing radiations, the magnitude of radiation effects likely to be

incurred by exposed persons. The quality factor for X-rays, gamma rays, and most beta particles is 1.0.

Rad (radiation absorbed dose): The unit of absorbed dose. One rad equals 100 ergs per gram.

Radiation Area: Any area accessible to individuals in which radiation levels could result in an individual

receiving a deep dose equivalent in excess of 0.005 rem (0.05 millisievert) in 1 hour at 30 centimeters from

the source or from any surface that the radiation penetrates. (10 CFR 835.2(a)).

Radiation source: A device or a material that is capable of emitting ionizing radiation.

Radiological worker: A general employee whose job assignment involves operation of radiation-

producing devices or working with radioactive materials, or who is likely to be routinely occupationally

exposed above 0.1 rem per year total effective dose equivalent. (10 CFR 835.2(a))

Radiological control technician (RCT): Any person who is actively engaged in or who has completed

facility-specific RCT training and qualification programs.

Rem (roentgen equivalent man): The unit of dose equivalence used for humans, which considers the

biological effects of different types of radiation. The dose equivalent in rem is numerically equal to the

absorbed dose in rad multiplied by the applicable quality factor.

Roentgen (R): The unit of exposure. One roentgen equals 2.58 x 10-4 coulomb per kilogram of air.

Scattered radiation: Radiation that has been deviated in direction as a result of interaction with matter

and has usually been reduced in energy.