§ 835.1 Scope. § 835.2 Definitions.
(a) As used in this part: Airborne radioactive material or airborne radioactivity means radioactive material in any chemical or physical form that is dissolved, mixed, suspended, or otherwise entrained in air. Airborne radioactivity area means any area where the measured concentration of airborne radioactivity, above natural background, exceeds or is likely to exceed 10 percent of the derived air concentration (DAC) values listed in appendix A or appendix C of this part. ALARA means ``As Low As is Reasonably Achievable,'' which is 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. As used in this part, ALARA is not a dose limit but a process which has the objective of attaining doses as far below the applicable limits of this part as is reasonably achievable. Ambient air means the general air in the area of interest (e.g., the general room atmosphere), as distinct from a specific stream or volume of air that may have different properties. 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. ALI is the smaller value of intake of a given radionuclide in a year by the reference man (ICRP Publication 23) that would result in a committed effective dose equivalent of 5 rems (0.05 sievert) or a committed dose equivalent of 50 rems (0.5 sievert) to any individual organ or tissue. ALI values for intake by ingestion and inhalation of selected radionuclides are based on 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. Background means radiation from: (i) Naturally occurring radioactive materials which have not been technologically enhanced; (ii) Cosmic sources; (iii) Global fallout as it exists in the environment (such as from the testing of nuclear explosive devices); (iv) Radon and its progeny in concentrations or levels existing in buildings or the environment which have not been elevated as a result of current or prior activities; and (v) Consumer products containing nominal amounts of radioactive material or producing nominal amounts of radiation. Bioassay means the determination of kinds, quantities, or concentrations, and, in some cases, locations of radioactive material in the human body, whether by direct measurement or by analysis, and evaluation of radioactive materials excreted or removed from the human body. Calibration means to adjust and/or determine either: (i) The response or reading of an instrument relative to a standard (e.g., primary, secondary, or tertiary) or to a series of conventionally true values; or (ii) The strength of a radiation source relative to a standard (e.g., primary, secondary, or tertiary) or conventionally true value. Contamination area means any area where contamination levels are greater than the values specified in appendix D of this part, but less than or equal to 100 times those levels. Continuous air monitor (CAM) means an instrument that continuously samples and measures the levels of airborne radioactive materials on a ``real-time'' basis and has alarm capabilities at preset levels. Contractor means any entity under contract with the Department of Energy with the responsibility to perform activities at a DOE site or facility. Controlled area means any area to which access is managed in order to protect individuals from exposure to radiation and/or radioactive material. Individuals who enter only the controlled area without entering radiological areas are not expected to receive a total effective dose equivalent of more than 100 mrem (0.001 sievert) in a year. Declared pregnant worker means a woman who has voluntarily declared to her employer, in writing, her pregnancy for the purpose of being subject to the occupational exposure limits to the embryo/fetus as provided in § 835.206. This declaration may be revoked, in writing, at any time by the declared pregnant worker. Derived air concentration (DAC) means, for the radionuclides listed in appendix A of this part, the airborne concentration that equals the ALI divided by the volume of air breathed by an average worker for a working year of 2000 hours (assuming a breathing volume of 2400 m^3 ). For the radionuclides listed in appendix C of this part, the air immersion DACs were 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. DOE activities means an activity taken for or by the DOE that has the potential to result in the occupational exposure of an individual to radiation or radioactive material. The activity may be, but is not limited to, design, construction, operation, or decommissioning. To the extent appropriate, the activity may involve a single DOE facility or operation or a combination of facilities and operations, possibly including an entire site. Entrance or access point means any location through which an individual could gain access to areas controlled for the purposes of radiation protection. This includes entry or exit portals of sufficient size to permit human entry, irrespective of their intended use. General employee means an individual who is either a DOE or DOE contractor employee; an employee of a subcontractor to a DOE contractor; or a visitor who performs work for or in conjunction with DOE or utilizes DOE facilities. High contamination area means any area where contamination levels are greater than 100 times the values specified in appendix D of this part. High radiation area means any area, accessible to individuals, in which radiation levels could result in an individual receiving a deep dose equivalent in excess of 0.1 rem (0.001 sievert) in 1 hour at 30 centimeters from the radiation source or from any surface that the radiation penetrates. Individual means any human being. Member of the public means an individual who is not occupationally exposed to radiation or radioactive material. An individual is not a ``member of the public'' during any period in which the individual receives occupational exposure. Minor means an individual less than 18 years of age. Monitoring means actions intended to detect and quantify radiological conditions. Nonstochastic effects means effects due to radiation exposure for which the severity varies with the dose and for which a threshold normally exists (e.g., radiation-induced opacities within the lens of the eye). Occupational exposure means an individual's exposure to ionizing radiation (external and internal) as a result of that individual's work assignment. Occupational exposure does not include planned special exposures, exposure received as a medical patient, background radiation, or voluntary participation in medical research programs. Person means any individual, corporation, partnership, firm, association, trust, estate, public or private institution, group, Government agency, any State or political subdivision of, or any political entity within a State, any foreign government or nation or other entity, and any legal successor, representative, agent or agency of the foregoing; provided that person does not include the Department or the United States Nuclear Regulatory Commission. Radiation means ionizing radiation: alpha particles, beta particles, gamma rays, X-rays, neutrons, high-speed electrons, high-speed protons, and other particles capable of producing ions. Radiation as used in this part, does not include non-ionizing radiation, such as radio- or micro-waves, or visible, infrared, or ultraviolet light. Radiation area means any area accessible to individuals in which radiation levels could result in an individual receiving a deep dose equivalent in excess of 0.005 rem (0.05 millisievert) in 1 hour at 30 centimeters from the source or from any surface that the radiation penetrates. Radiological area means any area within a controlled area which must be posted as a ``radiation area,'' ``high radiation area,'' ``very high radiation area,'' ``contamination area,'' ``high contamination area,'' or ``airborne radioactivity area'' in accordance with § 835.603. Radiological worker means a general employee whose job assignment involves operation of radiation producing devices or working with radioactive materials, or who is likely to be routinely occupationally exposed above 0.1 rem (0.001 sievert) per year total effective dose equivalent. Representative, as applied to the sampling of radioactive material, means sampling in such a manner that the sample closely approximates both the amount of activity and the physical and chemical properties of the material (e.g., particle size and solubility in the case of air sampling of the aerosol to which workers may be exposed). Stochastic effects means malignant and hereditary diseases for which the probability of an effect occurring, rather than its severity, is regarded as a function of dose without a threshold for radiation protection purposes. Survey means an evaluation of the radiological conditions and potential hazards incident to the production, use, transfer, release, disposal, or presence of radioactive material or other sources of radiation. When appropriate, such an evaluation includes a physical survey of the location of radioactive material and measurements or calculations of levels of radiation, or concentrations or quantities of radioactive material present. Very high radiation area means any area accessible to individuals in which radiation levels could result in an individual receiving an absorbed dose in excess of 500 rads (5 grays) in one hour at 1 meter from a radiation source or from any surface that the radiation penetrates. Year means the period of time beginning on or near January 1 used to determine compliance with the provisions of this part. The starting date of the year used to determine compliance may be changed provided that the change is made at the beginning of the year and that no day is omitted or duplicated in consecutive years. (b) As used in this part to describe various aspects of radiation dose: Absorbed dose (D) means the energy absorbed by matter from ionizing radiation per unit mass of irradiated material at the place of interest in that material. The absorbed dose is expressed in units of rad (or gray) (1 rad = 0.01 gray). Collective dose means the sum of the total effective dose equivalent values for all individuals in a specified population. Collective dose is expressed in units of person-rem (or person- sievert). Committed dose equivalent (HT,50) means the dose equivalent calculated to be received by a tissue or organ over a 50-year period after the intake of a radionuclide into the body. It does not include contributions from radiation sources external to the body. Committed dose equivalent is expressed in units of rem (or sievert). Committed effective dose equivalent (HE,50) means the sum of the committed dose equivalents to various tissues in the body (HT,50), each multiplied by the appropriate weighting factor (wT)-that is, HE,50 = SigmawTHT,50. Committed effective dose equivalent is expressed in units of rem (or sievert). Cumulative total effective dose equivalent means the sum of the total effective dose equivalents recorded for an individual for each year of employment at a DOE or DOE contractor site or facility, effective January 1, 1989. Deep dose equivalent means the dose equivalent derived from external radiation at a depth of 1 cm in tissue. Dose equivalent (H) means the product of absorbed dose (D) in rad (or gray) in tissue, a quality factor (Q), and other modifying factors (N). Dose equivalent is expressed in units of rem (or sievert) (1 rem = 0.01 sievert). Effective dose equivalent (HE) means 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 = SigmawTHT. It includes the dose from radiation sources internal and/or external to the body. The effective dose equivalent is expressed in units of rem (or sievert). External dose or exposure means that portion of the dose equivalent received from radiation sources (e.g., ``external sources'') outside the body. Extremity means hands and arms below the elbow or feet and legs below the knee. Internal dose or exposure means that portion of the dose equivalent received from radioactive material taken into the body (e.g., ``internal sources''). Lens of the eye dose equivalent means the external exposure of the lens of the eye and is taken as the dose equivalent at a tissue depth of 0.3 cm. Quality factor means the principal modifying factor used to calculate the dose equivalent from the absorbed dose; the absorbed dose (expressed in rad or gray) is multiplied by the appropriate quality factor (Q). (i) The quality factors to be used for determining dose equivalent in rem are shown below: Quality Factors ------------------------------------------------------------------------------ Radiation type | Quality | factor ------------------------------------------------------------------------------ | X-rays, gamma rays, positrons, electrons (including tritium | 1 beta particles). | Neutrons, <= 10 keV .......................................... | 3 Neutrons, > 10 keV .......................................... | 10 Protons and singly-charged particles of unknown energy with | 10 rest mass greater than one atomic mass unit. | Alpha particles and multiple-charged particles (and particles | 20 of unknown charge) of unknown energy. | ------------------------------------------------------------------------------ When spectral data are insufficient to identify the energy of the neutrons, a quality factor of 10 shall be used. (ii) When spectral data are sufficient to identify the energy of the neutrons, the following mean quality factor values may be used: QUALITY FACTORS FOR NEUTRONS - [Mean quality factors, Q (maximum value in a 30-cm dosimetry phantom), and values of neutron flux density that deliver in 40 hours, a maximum dose equivalent of 100 mrem (0.001 sievert).] ------------------------------------------------------------------------------ | Mean | Neutron Neutron energy (MeV) | quality | flux | factor | density (cm | | -2s-1) ------------------------------------------------------------------------------ | | 2.5 x 10^-8 thermal ........................... | 2 | 680 1 x 10^-7 ..................................... | 2 | 680 1 x 10^-6 ..................................... | 2 | 560 1 x 10^-5 ..................................... | 2 | 560 1 x 10^-4 ..................................... | 2 | 580 1 x 10^-3 ..................................... | 2 | 680 1 x 10^-2 ..................................... | 2.5 | 700 1 x 10^-1 ..................................... | 7.5 | 115 5 x 10^-1 ..................................... | 11 | 27 1 ............................................. | 11 | 19 2.5 ........................................... | 9 | 20 5 ............................................. | 8 | 16 7 ............................................. | 7 | 17 10 ............................................ | 6.5 | 17 14 ............................................ | 7.5 | 12 20 ............................................ | 8 | 11 40 ............................................ | 7 | 10 60 ............................................ | 5.5 | 11 1 x 10^2 ...................................... | 4 | 14 2 x 10^2 ...................................... | 3.5 | 13 3 x 10^2 ...................................... | 3.5 | 11 4 x 10^2 ...................................... | 3.5 | 10 ------------------------------------------------------------------------------ Shallow dose equivalent means the dose equivalent deriving from external radiation at a depth of 0.007 cm in tissue. Total effective dose equivalent (TEDE) means the sum of the effective dose equivalent (for external exposures) and the committed effective dose equivalent (for internal exposures). For purposes of compliance with this part, deep dose equivalent to the whole body may be used as effective dose equivalent for external exposures. Weighting factor (wT) means the fraction of the overall health risk, resulting from uniform, whole body irradiation, attributable to specific tissue (T). The dose equivalent to tissue, T, is multiplied by the appropriate weighting factor to obtain the effective dose equivalent contribution from that tissue. The weighting factors are as follows: Weighting Factors For Various Tissues ------------------------------------------------------------------------------ Organs or tissues, T | Weighting | factor, wT ------------------------------------------------------------------------------ | Gonads ...................................................... | 0.25 Breasts ..................................................... | 0.15 Red bone marrow ............................................. | 0.12 Lungs ....................................................... | 0.12 Thyroid ..................................................... | 0.03 Bone surfaces ............................................... | 0.03 Remainder{1}................................................. | 0.30 Whole body{2}................................................ | 1.00 ------------------------------------------------------------------------------ {1} ``Remainder'' means the five other organs or tissues with the highest dose (e.g., liver, kidney, spleen, thymus, adrenal, pancreas, stomach, small intestine, and upper large intestine). The weighting factor for each remaining organ or tissue is 0.06. {2} For the case of uniform external irradiation of the whole body, a weighting factor (wT) equal to 1 may be used in determination of the effective dose equivalent. Whole body means, for the purposes of external exposure, head, trunk (including male gonads), arms above and including the elbow, or legs above and including the knee. (c) Terms defined in the Atomic Energy Act and not defined in this part are used consistent with the meanings given in the Act. (d) As used in this part, words in the singular also include the plural and words in the masculine gender also include the feminine and vice versa, as the case may be.
§ 835.3 General rule.