Glossary - hdbk11080138

DOE-HDBK-1108-97

Radiological Training for Accelerator Facilities

Student's Guide

GLOSSARY

Accelerator: A device employing electrostatic or electromagnetic fields to input kinetic energy to

molecules, atomic, or subatomic particles, and capable of creating a radiological area.

Access control system: Engineered or administrative systems that manage radiation dose to personnel by

limiting personnel entry.

Actinide Transmutation: Transformation of actinides through neutron activation.

Activity: The rate at which a source emits radiation is called its activity. Activity is measured in terms

of the number of disintegrations that take place every second. The unit for activity used at DOE sites is

the curie (Ci). One curie is equal to 37 billion (3.7 x 1010) disintegrations per second.

Annual Limit on Intake (ALI): Means the derived limit for the amount of radioactive material taken

into the body of an adult worker by inhalation or ingestion in a year. (see 10CFR 835)

Attenuation: The process by which a beam of radiation is reduced in intensity when passing through

some material. It is the combination of absorption and scattering processes and leads to a decrease in

flux intensity.

Beam: A flow of electromagnetic or particulate radiation that is either collimated and generally

unidirectional, or divergent from a small source but restricted to a small solid angle.

Beam scrapers: Beam scrapers remove particles that have wandered from the central area of the beam.

Bremsstrahlung: Secondary photon radiation produced by deceleration of charged particles passing

through matter.

Collider: An accelerator in which two opposed beams of particles collide head-on.

Continuous Air Monitor (CAM): Instrument that continuously samples and measures the levels of

airborne radioactive materials on a "real time" basis and has alarm capabilities at preset levels.