49 CFR 175.701 – Separation distance requirements for packages containing Class 7 (radioactive) materials in passenger-carrying aircraft
(a) The following table prescribes the minimum separation distances that must be maintained in a passenger-carrying aircraft between Class 7 (radioactive) materials labeled RADIOACTIVE YELLOW-II or RADIOACTIVE YELLOW-III and passengers and crew:
| Transport index or sum of transport indexes of all packages in the aircraft or predesignated area | Minimum separation distances | |
|---|---|---|
| Centimeters | Inches | |
| 0.1 to 1.0 | 30 | 12 |
| 1.1 to 2.0 | 50 | 20 |
| 2.1 to 3.0 | 70 | 28 |
| 3.1 to 4.0 | 85 | 34 |
| 4.1 to 5.0 | 100 | 40 |
| 5.1 to 6.0 | 115 | 46 |
| 6.1 to 7.0 | 130 | 52 |
| 7.1 to 8.0 | 145 | 57 |
| 8.1 to 9.0 | 155 | 61 |
| 9.1 to 10.0 | 165 | 65 |
| 10.1 to 11.0 | 175 | 69 |
| 11.1 to 12.0 | 185 | 73 |
| 12.1 to 13.0 | 195 | 77 |
| 13.1 to 14.0 | 205 | 81 |
| 14.1 to 15.0 | 215 | 85 |
| 15.1 to 16.0 | 225 | 89 |
| 16.1 to 17.0 | 235 | 93 |
| 17.1 to 18.0 | 245 | 97 |
| 18.1 to 20.0 | 260 | 102 |
| 20.1 to 25.0 | 290 | 114 |
| 25.1 to 30.0 | 320 | 126 |
| 30.1 to 35.0 | 350 | 138 |
| 35.1 to 40.0 | 375 | 148 |
| 40.1 to 45.0 | 400 | 157 |
| 45.1 to 50.0 | 425 | 167 |
(b) When transported aboard passenger-carrying aircraft packages, overpacks or freight containers labeled Radioactive Yellow-II or Radioactive Yellow-III must be separated from live animals by a distance of at least 0.5 m (20 inches) for journeys not exceeding 24 hours, and by a distance of at least 1.0 m (39 inches) for journeys longer than 24 hours.
(c) Except as provided in paragraph (d) of this section, the minimum separation distances prescribed in paragraphs (a) and (b) of this section are determined by measuring the shortest distance between the surfaces of the Class 7 (radioactive) materials package and the surfaces bounding the space occupied by passengers or animals. If more than one package of Class 7 (radioactive) materials is placed in a passenger-carrying aircraft, the minimum separation distance for these packages shall be determined in accordance with paragraphs (a) and (b) of this section on the basis of the sum of the transport index numbers of the individual packages or overpacks.
(d) Predesignated areas. A package labeled RADIOACTIVE YELLOW-II or RADIOACTIVE YELLOW-III may be carried in a passenger-carrying aircraft in accordance with a system of predesignated areas established by the aircraft operator. Each aircraft operator that elects to use a system of predesignated areas shall submit a detailed description of the proposed system to the Associate Administrator for approval prior to implementation of the system. A proposed system of predesignated areas is approved if the Associate Administrator determines that it is designed to assure that:
(1) The packages can be placed in each predesignated area in accordance with the minimum separation distances prescribed in paragraph (a) of this section; and
(2) The predesignated areas are separated from each other by minimum distance equal to at least four times the distances required by paragraphs (a) and (b) of this section for the predesignated area containing packages with the largest sum of transport indexes.