Regulations 2(1) & 19
1. A Type B(U) package shall meet the requirements of Schedule 12 and the requirements of this Schedule.
2. A package for irradiated nuclear fuel with activity greater than 37 PBq shall be so designed that if it were subjected to the water immersion test specified in paragraph 17 of Part III of Schedule 15, there would be no rupture of the containment system.
3. Compliance with the permitted activity release limits shall depend neither upon filters nor upon a mechanical cooling system.
4. A package shall not include a pressure relief system from the containment system which would allow the release of radioactive material to the environment under the conditions of the tests specified in paragraphs 6–11 and 13–16 of Part III of Schedule 15.
5. A package shall be so designed that if it were at the maximum normal operating pressure and it were subjected to the tests specified in paragraphs 6–11 and 13–16 of Part III of Schedule 15, the level of strains in the containment system would not attain values which would adversely affect the package in such a way that it would fail to meet the applicable requirements.
6. A package shall not have a maximum normal operating pressure in excess of a gauge pressure of 700 kPa.
7. The maximum temperature of any surface readily accessible during transport of a package shall not exceed 85°C in the absence of insolation under the ambient condition specified in paragraph 5 of Schedule 12 and the package shall be carried under exclusive use, as specified in paragraph 4 of Schedule 12, if the maximum temperature exceeds 50°C. Account may be taken of barriers or screens to give protection to transport workers without the need for the barriers or screens being subject to any test.
8. A package shall be designed for an ambient temperature range from −40°C to +38°C.