Editorial Note on Part 173
Editorial Note: Nomenclature changes to part 173 appear at 70 FR 56098, Sept. 23, 2005.

§ 173.403 Definitions. For purposes of this subpart— A 1 means the maximum activity of special form Class 7 (radioactive) material permitted in a Type A package. This value is either listed in § 173.435 or may be derived in accordance with the procedures prescribed in § 173.433.
A 2 means the maximum activity of Class 7 (radioactive) material, other than special form material, LSA material, and SCO, permitted in a Type A package. This value is either listed in § 173.435 or may be derived in accordance with the procedures prescribed in § 173.433.
*Class 7 (radioactive) material* See the definition of *Radioactive material* in this section.
*Closed transport vehicle* means a transport vehicle or conveyance equipped with a securely attached exterior enclosure that during normal transportation restricts the access of unauthorized persons to the cargo space containing the Class 7 (radioactive) materials. The enclosure may be either temporary or permanent, and in the case of packaged materials may be of the “see-through” type, and must limit access from top, sides, and bottom.
*Consignment* means a package or group of packages or load of radioactive material offered by a person for transport in the same shipment.
*Containment system* means the assembly of components of the packaging intended to retain the Class 7 (radioactive) material during transport.
*Contamination* means the presence of a radioactive substance on a surface in quantities in excess of 0.4 Bq/cm2 for beta and gamma emitters and low toxicity alpha emitters or 0.04 Bq/cm2 for all other alpha emitters. There are two categories of contamination: ( 1 ) Fixed contamination means contamination that cannot be removed from a surface during normal conditions of transport.
( 2 ) Non-fixed contamination means contamination that can be removed from a surface during normal conditions of transport.
*Conveyance* means: ( 1 ) For transport by public highway or rail: any transport vehicle or large freight container;
( 2 ) For transport by water: any vessel, or any hold, compartment, or defined deck area of a vessel including any transport vehicle on board the vessel; and
( 3 ) For transport by aircraft, any aircraft.
*Criticality Safety Index (CSI)* means a number (rounded up to the next tenth) which is used to provide control over the accumulation of packages, overpacks or freight containers containing fissile material. The CSI for a package containing fissile material is determined in accordance with the instructions provided in 10 CFR 71.22, 71.23, and 71.59. The CSI for an overpack, freight container, consignment or conveyance containing fissile material packages is the arithmetic sum of the criticality safety indices of all the fissile material packages contained within the overpack, freight container, consignment or conveyance.
*Design* means the description of a special form Class 7 (radioactive) material, a package, packaging, or LSA-III, that enables those items to be fully identified. The description may include specifications, engineering drawings, reports showing compliance with regulatory requirements, and other relevant documentation.
*Deuterium* means, for the purposes of § 173.453, deuterium and any deuterium compound, including heavy water, in which the ratio of deuterium atoms to hydrogen atoms exceeds 1:5000.
*Exclusive use* means sole use by a single consignor of a conveyance for which all initial, intermediate, and final loading and unloading and shipment are carried out in accordance with the direction of the consignor or consignee where required by this subchapter. The consignor and the carrier must ensure that any loading or unloading is performed by personnel having radiological training and resources appropriate for safe handling of the consignment. The consignor must provide to the initial carrier specific written instructions for maintenance of exclusive use shipment controls, including the vehicle survey requirement of § 173.443(c) as applicable, and include these instructions with the shipping paper information provided to the carrier by the consignor.
*Exemption value* means either an exempt material activity concentration or an exempt consignment activity limit listed in the table in § 173.436, or determined according to the procedures described in § 173.433, and used to determine whether a given physically radioactive material is sufficiently radioactive to be subject to the HMR (see definition of radioactive material). An exemption value is different from an exemption, as specified under the definition for special permit in § 171.8 of this subchapter.
*Fissile material* means plutonium-239, plutonium-241, uranium-233, uranium-235, or any combination of these radionuclides. Fissile material means the fissile nuclides themselves, not material containing fissile nuclides, but does not include: Unirradiated natural uranium or depleted uranium; and natural uranium or depleted uranium that has been irradiated in thermal reactors only. Certain exceptions for fissile materials are provided in § 173.453.
*Freight container* means a reusable container having a volume of 1.81 cubic meters (64 cubic feet) or more, designed and constructed to permit it being lifted with its contents intact and intended primarily for containment of packages in unit form during transportation. A “small freight container” is one which has an internal volume of not more than 3.0 cubic meters (106 cubic feet). All other freight containers are designated as “large freight containers.”
*Graphite* means, for the purposes of § 173.453, graphite with a boron equivalent content less than 5 parts per million and density greater than 1.5 grams per cubic centimeter.
*Highway route controlled quantity* means a quantity within a single package which exceeds: ( 1 ) 3,000 times the A1 value of the radionuclides as specified in § 173.435 for special form Class 7 (radioactive) material;
( 2 ) 3,000 times the A2 value of the radionuclides as specified in § 173.435 for normal form Class 7 (radioactive) material; or
( 3 ) 1,000 TBq (27,000 Ci), whichever is least.
*Limited quantity of Class 7 (radioactive) material* means a quantity of Class 7 (radioactive) material not exceeding the material's package limits specified in § 173.425 and conforming with requirements specified in § 173.421.
*Low Specific Activity (LSA) material* means Class 7 (radioactive) material with limited specific activity which is not fissile material or is excepted under § 173.453, and which satisfies the descriptions and limits set forth below. Shielding material surrounding the LSA material may not be considered in determining the estimated average specific activity of the LSA material. LSA material must be in one of three groups: ( 1 ) LSA-I: ( i ) Uranium and thorium ores, concentrates of uranium and thorium ores, and other ores containing naturally occurring radionuclides which are intended to be processed for the use of these radionuclides; or
( ii ) Natural uranium, depleted uranium, natural thorium or their compounds or mixtures, provided they are unirradiated and in solid or liquid form; or
( iii ) Radioactive material for which the A2 value is unlimited; or
( iv ) Other radioactive material in which the activity is distributed throughout and the estimated average specific activity does not exceed 30 times the values for activity concentration specified in § 173.436 or calculated in accordance with § 173.433, or 30 times the default values listed in Table 8 of § 173.433.
( 2 ) LSA-II: ( i ) Water with tritium concentration up to 0.8 TBq/L (20.0 Ci/L); or
( ii ) Other radioactive material in which the activity is distributed throughout and the average specific activity does not exceed 10−4 A2/g for solids and gases, and 10−5 A2/g for liquids.
( 3 ) LSA-III. Solids (*e.g.,* consolidated wastes, activated materials), excluding powders, that meet the requirements of § 173.468 and in which: ( i ) The radioactive material is distributed throughout a solid or a collection of solid objects, or is essentially uniformly distributed in a solid compact binding agent (such as concrete, bitumen, ceramic, etc.);
( ii ) The radioactive material is relatively insoluble, or it is intrinsically contained in a relatively insoluble material, so that, even under loss of packaging, the loss of Class 7 (radioactive) material per package by leaching when placed in water for seven days would not exceed 0.1 A2; and
( iii ) The estimated average specific activity of the solid, excluding any shielding material, does not exceed 2 × 10−3 A2/g.
*Low toxicity alpha emitters* means natural uranium; depleted uranium; natural thorium; uranium-235 or uranium-238; thorium-232; thorium-228 and thorium-230 when contained in ores or physical and chemical concentrates; and alpha emitters with a half-life of less than 10 days.
*Maximum normal operating pressure* means the maximum gauge pressure that would develop in a containment system during a period of one year, in the absence of venting or cooling, under the heat conditions specified in 10 CFR 71.71(c)(1).
*Multilateral approval* means approval of a package design or shipment by the relevant Competent Authority of the country of origin and of each country through or into which the package or shipment is to be transported. This definition does not include approval from a country over which Class 7 (radioactive) materials are carried in aircraft, if there is no scheduled stop in that country.
*Natural thorium* means thorium with the naturally occurring distribution of thorium isotopes (essentially 100 percent by weight of thorium-232).
*Normal form Class 7 (radioactive) material* means Class 7 (radioactive) which has not been demonstrated to qualify as “special form Class 7 (radioactive) material.”
*Package* means the packaging together with its radioactive contents as presented for transport. ( 1 ) “Excepted package” means a packaging together with its excepted Class 7 (radioactive) materials as specified in §§ 173.421-173.426 and 173.428.
( 2 ) “Industrial package” means a packaging that, together with its low specific activity (LSA) material or surface contaminated object (SCO) contents, meets the requirements of §§ 173.410 and 173.411. Industrial packages are categorized in § 173.411 as either: ( i ) “Industrial package Type 1 (Type IP-1);
( ii ) “Industrial package Type 2 (Type IP-2); or
( iii ) “Industrial package Type 3 (Type IP-3).
( 3 ) “Type A package” means a packaging that, together with its radioactive contents limited to A1 or A2 as appropriate, meets the requirements of §§ 173.410 and 173.412 and is designed to retain the integrity of containment and shielding required by this part under normal conditions of transport as demonstrated by the tests set forth in § 173.465 or § 173.466, as appropriate. A Type A package does not require Competent Authority approval.
( 4 ) “Type B package” means a packaging designed to transport greater than an A1 or A2 quantity of radioactive material that, together with its radioactive contents, is designed to retain the integrity of containment and shielding required by this part when subjected to the normal conditions of transport and hypothetical accident test conditions set forth in 10 CFR part 71. ( i ) “Type B(U) package” means a Type B packaging that, together with its radioactive contents, for international shipments requires unilateral approval only of the package design and of any stowage provisions that may be necessary for heat dissipation.
( ii ) “Type B(M) package” means a Type B packaging, together with its radioactive contents, that for international shipments requires multilateral approval of the package design, and may require approval of the conditions of shipment. Type B(M) packages are those Type B package designs which have a maximum normal operating pressure of more than 700 kPa/cm2 (100 lb/in2) gauge or a relief device which would allow the release of Class 7 (radioactive) material to the environment under the hypothetical accident conditions specified in 10 CFR part 71.
( 5 ) “Fissile material package” means a packaging, together with its fissile material contents, which meets the requirements for fissile material packages described in subpart E of 10 CFR 71. A fissile material package may be a Type AF package, a Type B(U)F package, or a Type B(M)F package.
*Packaging* means, for Class 7 (radioactive) materials, the assembly of components necessary to ensure compliance with the packaging requirements of this subpart. It may consist of one or more receptacles, absorbent materials, spacing structures, thermal insulation, radiation shielding, service equipment for filling, emptying, venting and pressure relief, and devices for cooling or absorbing mechanical shocks. The conveyance, tie-down system, and auxiliary equipment may sometimes be designated as part of the packaging.
*Quality assurance* means a systematic program of controls and inspections applied by each person involved in the transport of radioactive material which provides confidence that a standard of safety prescribed in this subchapter is achieved in practice.
*Radiation level* means the radiation dose-equivalent rate expressed in millisieverts per hour or mSv/h (millirems per hour or mrem/h). It consists of the sum of the dose-equivalent rates from all types of ionizing radiation present including alpha, beta, gamma, and neutron radiation. Neutron flux densities may be used to determine neutron radiation levels according to Table 1: Table 1—Neutron Fluence Rates To Be Regarded as Equivalent to a Radiation Level of 0.01 mSv/h (1mrem/h) 1
Energy of neutron
Flux density equivalent to 0.01 mSv/h(1 mrem/h)neutrons per squarecentimeterper second(n/cm2/s)1 Thermal (2.5 10E-8) MeV
272.0 1 keV
272.0 10 keV
281.0 100 keV
47.0 500 keV
11.0 1 MeV
7.5 5 MeV
6.4 10 MeV
6.7 1 Flux densities equivalent for energies between those listed in this table may be obtained by linear interpolation.
*Radioactive contents* means a Class 7 (radioactive) material, together with any contaminated or activated solids, liquids and gases within the packaging.
*Radioactive instrument or article* means any manufactured instrument or article such as an instrument, clock, electronic tube or apparatus, or similar instrument or article having Class 7 (radioactive) material in gaseous or non-dispersible solid form as a component part.
*Radioactive material* means any material containing radionuclides where both the activity concentration and the total activity in the consignment exceed the values specified in the table in § 173.436 or values derived according to the instructions in § 173.433.
*Special form Class 7 (radioactive) material* means either an indispersible solid radioactive material or a sealed capsule containing radioactive material which satisfies the following conditions: ( 1 ) It is either a single solid piece or a sealed capsule containing radioactive material that can be opened only by destroying the capsule;
( 2 ) The piece or capsule has at least one dimension not less than 5 mm (0.2 in); and
( 3 ) It satisfies the test requirements of § 173.469. Special form encapsulations designed in accordance with the requirements of § 173.389(g) in effect on June 30, 1983 (see 49 CFR part 173, revised as of October 1, 1982), and constructed prior to July 1, 1985 and special form encapsulations designed in accordance with the requirements of § 173.403 in effect on March 31, 1996 (see 49 CFR part 173, revised as of October 1, 1995), and constructed prior to April 1, 1997, may continue to be used. Any other special form encapsulation must meet the requirements of this paragraph (3).
*Specific activity* of a radionuclide means the activity of the radionuclide per unit mass of that nuclide. The specific activity of a material in which the radionuclide is essentially uniformly distributed is the activity per unit mass of the material.
*Surface Contaminated Object (SCO)* means a solid object which is not itself radioactive but which has radioactive material distributed on its surface. SCO exists in two phases: ( 1 ) SCO-I: A solid object on which: ( i ) The non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 Bq/cm2 (10−4 microcurie/cm2) for beta and gamma and low toxicity alpha emitters, or 0.4 Bq/cm2 (10−5 microcurie/cm2) for all other alpha emitters;
( ii ) The fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 (1.0 microcurie/cm2) for beta and gamma and low toxicity alpha emitters, or 4 × 103 Bq/cm2 (0.1 microcurie/cm2) for all other alpha emitters; and
( iii ) The non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 4 × 104 Bq/cm2 (1 microcurie/cm2) for beta and gamma and low toxicity alpha emitters, or 4 × 103 Bq/cm2 (0.1 microcurie/cm2) for all other alpha emitters.
( 2 ) SCO-II: A solid object on which the limits for SCO-I are exceeded and on which: ( i ) The non-fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 400 Bq/cm2 (10−2 microcurie/cm2) for beta and gamma and low toxicity alpha emitters, or 40 Bq/cm2 (10−3 microcurie/cm2) for all other alpha emitters;
( ii ) The fixed contamination on the accessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 (20 microcurie/cm2) for beta and gamma and low toxicity alpha emitters, or 8 × 104 Bq/cm2 (2 microcuries/cm2) for all other alpha emitters; and
( iii ) The non-fixed contamination plus the fixed contamination on the inaccessible surface averaged over 300 cm2 (or the area of the surface if less than 300 cm2) does not exceed 8 × 105 Bq/cm2 (20 microcuries/cm2) for beta and gamma and low toxicity alpha emitters, or 8 × 104 Bq/cm2 (2 microcuries/cm2) for all other alpha emitters.
*Transport index (TI)* means the dimensionless number (rounded up to the next tenth) placed on the label of a package, to designate the degree of control to be exercised by the carrier during transportation. The transport index is determined by multiplying the maximum radiation level in millisieverts (mSv) per hour at 1 m (3.3 ft) from the external surface of the package by 100 (equivalent to the maximum radiation level in millirem per hour at 1 m (3.3 ft)).
*Type A quantity* means a quantity of Class 7 (radioactive) material, the aggregate radioactivity which does not exceed A1 for special form Class 7 (radioactive) material of A2 for normal form Class 7 (radioactive) material, where A1 and A2 values are given in § 173.435 or are determined in accordance with § 173.433.
*Type B quantity* means a quantity of material greater than a Type A quantity.
*Unilateral approval* means approval of a package design solely by the Competent Authority of the country of origin of the design.
*Unirradiated thorium* means thorium containing not more than 10−7 grams uranium-233 per gram of thorium-232.
*Unirradiated uranium* means uranium containing not more than 2 × 103 Bq of plutonium per gram of uranium-235, not more than 9 × 106 Bq of fission products per gram of uranium-235 and not more than 5 × 10−3 g of uranium-236 per gram of uranium-235.
*Uranium* —*natural, depleted* or *enriched* means the following: ( 1 ) ( i ) “Natural uranium” means uranium (which may be chemically separated) containing the naturally occurring distribution of uranium isotopes (approximately 99.28% uranium-238 and 0.72% uranium-235 by mass).
( ii ) “Depleted uranium” means uranium containing a lesser mass percentage of uranium-235 than in natural uranium.
( iii ) “Enriched uranium” means uranium containing a greater mass percentage of uranium-235 than 0.72%.
( 2 ) For each of these definitions, a very small mass percentage of uranium-234 may be present.
[69 FR 3670, Jan. 26, 2004; 69 FR 55116, Sept. 13, 2004; 69 FR 58843, Oct. 1, 2004; 70 FR 56098, Sept. 23, 2005; 70 FR 73165, Dec. 9, 2005; 79 FR 40610, July 11, 2014; 80 FR 1162, Jan. 8, 2015]