ONR’s Expectations of Shielding Design in package Design Safety Reports

Background:This paper communicates ONR’s expectations of package designs, following changes to IAEA regulations. GB legislation for land transport requires from July 2015, all new package designs, modifications and renewals meet the shielding requirements in SSR-6 2012.Change to the Regulations:ONR historically required operational controls to ensure dose limits will be met for routine conditions of transport. This is now a design requirement following the introduction in SSR-6 of Paragraph 617, which ensures packages are designed to carry maximum contents without exceedingstatutory radiation levels. Package and conveyance dose rates must be demonstrated within the design process and by operational controls. Requirements for compliance with normal/ accident conditions are unchanged.Demonstration of Shielding Design:The compliance demonstration should be commensurate with the hazard and safety margin. Routine Conditions: Compliance with radiation dose levels for the intended content. Also consider conveyance (vehicle) dose rates.Normal Conditions: As RCT, and designs for IP-2, IP-3, Type A, B and C packages should prevent external surface dose rates increasing by >20% following NCT tests.Accident Conditions: As RCT and NCT, and designs for Type B and C packages should prevent dose rates at 1m from a package from exceeding 10mSv/h following ACT testing.Competent Authority Approved Designs:For existing approvals, any periodic renewal or modification must address the requirements of SSR-6. ONR will conclude either:The package is compliant with SSR-6: Five year certificate, possibly with advice.The application contains some minor shortfalls, however ONR is confident that the design meets the regulations: Short term certificate, possibly with operational limits. This permits transport for a limited period whilst evidence of compliance is prepared. The application contains safety significant shortfalls: ONR is not confident the design meets regulations. The application will be declined.Self-Approved Packages:This approach applies for self-approved packages, commensurate with the hazard. ONR expects self-approved packages under TS-R-1, intended for use post-June 2015, to be approved under SSR-6 at the next renewal (<5 years). Consignors are responsible for ensuring all regulatory requirements are met.