AFI-48-125(AF-dosime..

AFI48-125 1 MARCH 1999 37
a tissue depth of 1 cm (1000 mg/ cm 2 ) beneath the outer surface of the skin.
Derived Air Concentration (DAC)—The concentration of a given radionuclide in air which, if breathed
by the reference man for a working year of 2,000 hours under conditions of light work (inhalation rate 1.2
cubic meters of air per hour), results in an intake of one ALI. DAC values are given in Table 1, Column
3, of appendix B to Secs. 20.1001-20.2401.
Derived Air Concentration-hour (DAC-hour)—The product of the concentration of radioactive
material in air (expressed as a fraction or multiple of the derived air concentration for each radionuclide)
and the time of exposure to that radionuclide, in hours. A licensee may take 2,000 DAC-hours to represent
one ALI, equivalent to a committed effective dose equivalent of 5 rems (0.05 Sv).
dose (radiation dose)—A generic term that includes: absorbed dose, dose equivalent (HT ), effective
dose equivalent (HE ), committed dose equivalent (CDE), committed effective dose equivalent (CEDE),
or total effective dose equivalent (TEDE).
Dose equivalent (HT )—The product of the absorbed dose in tissue (DT ) and the quality factor (Q) , and
all other necessary modifying factors at the location of interest where HT = DTQ. The units of dose
equivalent are the rem and sievert (Sv) (1 rem = 0.01 sievert). The dose equivalent in Sv is equal to the
absorbed dose in grays multiplied by the Q; 1 Sv = 100 rems. Its purpose is to have a single unit,
regardless of the type of radiation, describing the radiation effect on man. See also Deep Dose equivalent,
Eye-Dose equivalent, and Shallow-Dose equivalent
dosimetry processor—An individual or organization that processes and evaluates individual monitoring
equipment in order to determine the radiation dose delivered to the equipment.
dosimeter—A device that detects and measures accumulated ionizing radiation dose received by
occupationally exposed individuals. The Dosimetry program uses thermoluminescent dosimeters (TLD).
Examples of other types of dosimeters include film badges, pocket ionization chambers, electronic
personnel dosimeters (EPD), and CR-39 fast neutron detectors.
Effective Dose Equivalent (EDE) (HE )—The sum of the products of the dose equivalent to the organ or
tissue (HT ) and the weighting factors (wT) applicable to each of the body organs or tissues that are
irradiated (HE = Σ WTHT ). It provides a means for handling radiation situations, varying organ
sensitivities, and so on and for correlating all exposures to their relative effect on the whole body.
embryo/fetus—The developing human organism from conception until the time of birth.
entrance or access point—Any location through which an individual could gain access to radiation areas
or to radioactive materials. This includes entry or exit portals of sufficient size to permit human entry,
irrespective of their intended use.
Exposure—Ionizing radiation may be either produced from machines (x-ray machines, accelerators, etc.)
or spontaneously emitted by radioactive material. An individual located near such machines or materials
may be "exposed" to the ionizing radiation emitted therefrom; hence, sustain an exposure.
external dose—The portion of the dose equivalent received from radiation sources or devices outside the
body.
external Emitter—A radionuclide or ionizing radiation producing device which is located external to the
body.