Anode

DOE-HDBK-1109-97

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

Instructor's Guide

Anode: The positive electrode in an X-ray device that emits X-rays after being struck by energetic

electrons from the cathode.

Aperture: In this context, the opening within an X-ray source housing that permits the primary X-ray

beam to emerge in the intended direction. Such an aperture is not necessarily an open hole, but rather may

be a portion of the metal wall of the X-ray source housing that is significantly thinner than the surrounding

X-ray source housing walls.

Attenuation: The reduction of a radiation quantity upon passage of the radiation through matter, resulting

from all types of interaction with that matter. The radiation quantity may be, for example, the particle

fluency rate.

As low as reasonably achievable (ALARA): Means the approach to radiation protection to manage and

control exposures (both individual and collective) to the work force and to the general public to as low as

is reasonable, taking into account social, technical, economic, practical and public policy considerations.

ALARA is not a dose limit but a process which has the objective of attaining doses as far below the

applicable limits of 10 CFR 835 as is reasonably achievable. (10 CFR 835.2(a))

Bremsstrahlung: The electromagnetic radiation emitted when an electrically charged subatomic particle,

such as an electron, loses energy upon being accelerated and deflected by the electric field surrounding an

atomic nucleus. In German, the term means braking radiation.

Cabinet X-ray system: An industrial X-ray device with the X-ray tube installed in an enclosure (cabinet)

that, independent of existing architectural structures except the floor upon which it may be placed, is

intended to contain at least that portion of a material being irradiated, provide radiation attenuation, and

exclude individuals from its interior during X-ray generation. Included are all X-ray devices designed

primarily for the inspection of carry-on baggage at airline, railroad, and bus terminals. Excluded from this

definition are X-ray devices using a building wall for shielding and those using portable shields on a

temporary basis.

Cathode: The negative electrode that emits electrons in an X-ray device.