Considerations for neglecting water leakage in the criticality analysis of individual packages

Current transport regulations specify that the criticality analysis of an individual package shall assume that water can leak into or out of all void spaces in the package, including those within the containment system. However, if the packaging design incorporates special features to prevent such leakage, these regulations permit the absence of water to be assumed. This paper describes the special features listed in the regulations, discusses differences between subcriticality and other regulatory performance requirements, and presents additional considerations that should be addressed to justify that water leakage may be neglected in the criticality analysis of individual packages. The assumption of no water leakage should be considered as an exception that is appropriate only in those instances in which its benefits clearly outweigh the additional risk. Justification of this assumption will generally necessitate an increase in design margin and a substantial effort in package evaluation, operating procedures, acceptance testing, maintenance, and quality assurance programs. (authors)