t International Commission on Radiological Protection. Abbreviation for meter. micron: One-millionth of a meter. ml: Milliliter = 0.001 liters. Maximum permissible concentration (of a radionuclide) in air. The average con- MPCs: centration above background of a specific radionuclide to which an individual can be exposed without exceeding the guidelines. MPCw: . Maximum permissible concentration MPLB: Maximum permissible lung burden. yadionuclide) ‘above. ) in water. (of a (See definition MPLD: Maximum permissible lung dose. NCRP: National Council on Radiation Protection and Measurements. ay Abbreviation for nanocurie, which is one- billionth of a curie, or 1079 curie. Abbreviation for picocurie, which is one- millionth of a microcurie, or 10712 curies. Abbreviation for Quality Factor, which is assigned on the basis cf a number of censiderations. A quality factor is a modifyinca factor used in calculation of dose equivalent whicn accounts for differences y in producing biological effects among various forms of radiation (e.g., alpha, and X-radiation). * Rad: Unit of absorbed dose ergs/gram. (DBD), which is 103 The rad is a measure of the erergy imparted to matter by ionizing radiation per unit mass of irradiated Material at the place of in cr — Radionuclide: A nuclide cf an element trat is raeéloective.