DHS 157.03(397)(397)“Type A quantity” means a quantity of radioactive material, the aggregate radioactivity of which does not exceed A1 for special form radioactive material or A2 for normal form radioactive material, where A1 and A2 are given in ch. DHS 157 Appendix O or may be determined by procedures described in ch. DHS 157 Appendix O.
DHS 157.03(398)(398)“Type B package” means a packaging that, together with its radioactive contents, is designed to retain the integrity of containment and shielding required by 49 CFR 173 when subjected to the normal conditions of transport and hypothetical accident test conditions set forth in 10 CFR 71.
DHS 157.03 NoteNote: A Type B package design is designated as B(U) or B(M). B(U) refers to the need for unilateral approval of international shipments; B(M) refers to the need for multilateral approval. No distinction is made in how packages with these designations may be used in domestic transportation. To determine their distinction for international transportation, refer to 49 CFR Part 173. A Type B package approved prior to September 6, 1983 was designated only as Type B.
DHS 157.03(399)(399)“Type B quantity” means a quantity of radioactive material greater than a type A quantity.
DHS 157.03(400)(400)“Type of use” means use of radioactive material as specified in s. DHS 157.63 (1) or (2), 157.64 (1), 157.65 (1), 157.66 (1) or 157.67 (1).
DHS 157.03(401)(401)“Underwater irradiator” means an irradiator in which the sources always remain shielded under water and humans do not have access to the sealed sources or the space subject to irradiation without entering the pool.
DHS 157.03(402)(402)“Underwater radiography” means industrial radiography performed when the radiographic exposure device and related equipment are beneath the surface of the water.
DHS 157.03(402g)(402g)“Unescorted access” means solitary access to a category 1 or category 2 quantity of radioactive material or the devices that contain the material.
DHS 157.03(402m)(402m)“Unirradiated uranium” means uranium containing not more than 2 X 103 Bq of plutonium per gram of uranium-235, not more than 9 X 106 Bq of fission products per gram of uranium-235, and not more than 5 X 10-3 g of uranium-236 per gram of uranium-235.
DHS 157.03(403)(403)“Unit dosage” means a quantity of radioactive material that meets all the following criteria:
DHS 157.03(403)(a)(a) Is obtained or prepared under the requirements in s. DHS 157.63 (1) or (2) or 157.64 (1).
DHS 157.03(403)(b)(b) Is to be administered as a single dosage to a patient or human research subject without any further manipulation of the dosage after it is initially prepared, except to adjust the dosage to patient needs.
DHS 157.03(404)(404)“Unrefined and unprocessed ore” means ore in its natural form prior to any processing, such as grinding, roasting or beneficiating, or refining the ore from its natural state. Processing does not include sieving or encapsulation of ore or preparation of samples for laboratory analysis.
DHS 157.03(405)(405)“Unrestricted area” or “uncontrolled area” means an area, access to which is neither limited nor controlled by the licensee or registrant.
DHS 157.03(406)(406)“Uranium sinker bar” means a weight containing depleted uranium used to pull a logging tool down toward the bottom of a well.
DHS 157.03(407)(407)“Useful beam” means the radiation which passes through the tube housing port and the aperture of the beam-limiting device when the exposure switch or timer is activated.
DHS 157.03(408)(408)“User seal check” means an action conducted by the respirator user to determine if the respirator is properly seated to the face. Examples include negative pressure check, positive pressure check, irritant smoke check, or isoamyl acetate check.
DHS 157.03(409)(409)“Variable-aperture beam-limiting device” means a beam-limiting device that has capacity for stepless adjustment of the x-ray field size at a given SID.
DHS 157.03(410)(410)“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 5 Gy (500 rad) in one hour at one meter from a source of radiation or one meter from any surface that the radiation penetrates.
DHS 157.03(411)(411)“Virtual source” means a point from which radiation appears to originate.
DHS 157.03(412)(412)“Visible area” means that portion of the input surface of the image receptor over which incident x-ray photons are producing a visible image.
DHS 157.03(413)(413)“Waste” means those low-level radioactive wastes containing source, special nuclear, or byproduct material that are acceptable for disposal in a land disposal facility. For the purposes of this definition, “low-level radioactive waste” means radioactive waste not classified as high-level radioactive waste, transuranic waste, spent nuclear fuel, or byproduct material as defined in sub. (50) (b) to (e).
DHS 157.03(414)(414)“Waste handling licensee” mean a person licensed to receive and store radioactive residue prior to disposal and a person licensed to dispose of radioactive residue.
DHS 157.03(415)(415)“Wedge filter” means a filter which effects continuous change in transmission over all or a part of the useful beam.
DHS 157.03(416)(416)“Week” means 7 consecutive days starting on Sunday.
DHS 157.03(417)(417)“Weighting factor” or “wT” for an organ or tissue 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 of wT are:
Organ Dose Weighting Factors
Organ or Tissue   wT
Gonads   0.25