Glossary cont'd - hdbk110697

DOE-HDBK-1106-97

GLOSSARY (continued)

calculated for a continuous, non-shielded exposure via immersion in a semi-infinite atmospheric cloud.

The value is based upon the derived airborne concentration found in Table 1 of the U.S. Environmental

Protection Agency's Federal Guidance Report No. 11, Limiting Values of Radionuclide Intake and Air

Concentration and Dose Conversion Factors for Inhalation, Submersion, and Ingestion, published

September 1988. This document is available from the National Technical Information Service,

Springfield, VA.

Disintegration, Nuclear: A spontaneous nuclear transformation (radioactivity) characterized by the

emission of energy and/or mass from the nucleus. When numbers of nuclei are involved, the process is

characterized by a definite half-life.

Dose Terms:

Committed Dose Equivalent: The calculated dose equivalent projected to be received by a tissue or

organ over a 50-year period after an intake of radionuclide into the body. It does not include

contributions from external dose.

Committed Effective Dose Equivalent: The sum of the committed dose equivalents to various

tissues in the body, each multiplied by its weighting factor.

Cumulative Annual Effective Dose Equivalent: The sum of the annual effective dose equivalents

recorded for an individual for each year of employment.

Dose Equivalent: The product of absorbed dose (D) in rad (or gray) in tissue, a quality factor (Q),

and other modifying factors (N).

Effective Dose Equivalent: The summation of the products of the dose equivalent received by

specified tissues of the body (HT) and the appropriate weighting factor (wT)--that is, HE = EwTHT. It

includes the dose from radiation sources internal and/or external to the body.

Dosimeter: A portable instrument for measuring and registering the total accumulated dose to ionizing

radiation.

Dosimetry: The theory and application of the principles and techniques involved in the measurement and

recording of radiation doses. Its practical aspect is concerned with the use of various types of radiation

instruments with which measurements are made.