Glossary cont'd - hdbk110997

DOE-HDBK-1109-97

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

Instructor=s Guide

Collimator: A device used to limit the size, shape, and direction of the primary beam.

Compliance label: A label affixed to an intentional X-ray device certifying that the device has been

surveyed and that safe operating requirements have been met.

Control panel: A device containing the means for regulating and activating X-ray equipment or for

preselecting and indicating operating factors.

Controlled Area: Any area to which access is managed to protect individuals from exposure to radiation

and/or radioactive material. (10 CFR 835.2(a))

Dark current: A current, usually of electrons, that may flow through an acceleration tube or wave guide

from sources other than the cathode of the accelerator. This is an abnormal phenomenon, often associated

with poor vacuum conditions or contaminated surfaces in the acceleration region.

Door: In this context, any barrier that is designed to be moved or opened for routine operation purposes,

does not require tools to open, and permits access to the interior of the cabinet.

Dose equivalent: The product of absorbed dose, a quality factor, and other modifying factors. The unit of

dose equivalent is the rem. (10 CFR 835.2 (b))

Dosimeter: A device that measures and indicates radiation dose.

Electron volt (eV): A unit of energy equal to the energy gained by an electron passing through a potential

difference of 1 volt.

Enclosed beam system: An analytical X-ray system in which all possible X-ray paths (primary as well as

diffracted beams) are fully enclosed.

Exempt shielded installation: An X-ray installation in which the source of radiation and all objects

exposed to that source are within a permanent enclosure that meets the requirements of a shielded