Appendix D. In this context a sealed source is defined as radioactive material that is

sealed in a capsule or closely bonded, in a solid form and which is not exempt from regulatory control. It does not mean material encapsulated solely for disposal, or nuclear material contained in any fuel assembly, subassembly, fuel rod, or fuel pellet. Category 1 nationally tracked sources are those containing radioactive material at a quantity equal to or greater than the Category 1 threshold. Category 2 nationally tracked sources are those containing radioactive material at a quantity equal to or greater than the Category 2 threshold but less than the Category 1 threshold. Nonstochastic Effect means a health effect, the severity of which varies with the dose and for which a threshold is believed to exist. Radiation-induced cataract formation is an example of a nonstochastic effect. For purposes of 105 CMR 120.000: Deterministic Effect is an equivalent term. Planned Special Exposure means an infrequent exposure to radiation, separate from and in addition to the annual occupational dose limits. Quarter means a period of time equal to ¼ of the year observed by the licensee or registrant, approximately 13 consecutive weeks, providing that the beginning of the first quarter in a year coincides with the starting date of the year and that no day is omitted or duplicated in consecutive quarters. Reference Man means a hypothetical aggregation of human physical and physiological characteristics determined by international consensus. These characteristics may be used by researchers and public health employees to standardize results of experiments and to relate biological insult to a common base. A description of Reference Man is contained in the International Commission on Radiological Protection report, ICRP Publication 23, Report of the Task Group on Reference Man. Respiratory Protective Device means an apparatus, such as a respirator, used to reduce an individual's intake of airborne radioactive materials. Sanitary Sewerage means a system of public sewers for carrying off waste water and refuse, but excluding sewage treatment facilities, septic tanks, and leach fields owned or operated by the licensee or registrant. Stochastic Effect means a health effect that occurs randomly and for which the probability of the effect occurring, rather than its severity, is assumed to be a linear function of dose without threshold. Hereditary effects and cancer incidence are examples of stochastic effects. For purposes of 105 CMR 120.000: Probabilistic Effect is an equivalent term. Very High Radiation Area means an area, accessible to individuals, in which radiation levels from radiation sources external to the body could result in an individual receiving an absorbed dose in excess of 500 rads (five grays) in one hour at one meter from a source of radiation or from any surface that the radiation penetrates. (At very high doses received at high dose rates, units of absorbed dose, gray and rad, are appropriate, rather than units of dose equivalent, sievert and rem.) T Weighting Factor W for an Organ or Tissue (T) means the proportion of the risk of stochastic effects resulting from irradiation of that organ or tissue to the total risk of stochastic effects when the whole body is irradiated uniformly. For calculating the effective dose equivalent, the values T of W are: ORGAN DOSE WEIGHTING FACTORS Organ or Tissue T w Gonads 0.25 Breast 0.15 Red bone marrow 0.12 Lung 0.12 Thyroid 0.03 Bone surfaces 0.03 Remainder 0.30* Whole Body 1.00** 0.30 results from 0.06 for each of 5 "remainder" organs, excluding the skin and the lens of the * eye, that receive the highest doses. For the purpose of weighting the external whole body dose, for adding it to the internal dose, a ** T single weighting factor, w = 1.0, has been specified. The use of other weighting factors for external exposure will be approved on a case-by-case basis until such time as specific guidance is issued. 120.204 Implementation (A) Any existing license or certificate of registration condition that is more restrictive than 105 CMR 120.200 remains in force until there is an amendment or renewal of the license or registration. (B) If a license or certificate of registration condition exempts a licensee or registrant from a provision of 105 CMR 120.200 in effect on or before July 9, 1999, it also exempts the licensee or registrant from the corresponding provision of 105 CMR 120.200. (C) If a license or registration condition cites provisions of 105 CMR 120.200 in effect prior to July 9, 1999, which do not correspond to any provisions of the revised 105 CMR 120.200, the license or registration condition remains in force until there is an amendment or renewal of the license or registration that modifies or removes this condition.