Interesting article. Fundamental to all NHTSA covered products is the CFR (Code of Federal Regulations), It is the law. It is best to understand not only the binary requirements of said code but also the intention. Generally the codes have logical origins in the development. As well, it is generally a best practice to not just barely meet the law/code but exceed it to some degree. Test to test there will be variability and one may avoid hassles recall/lawsuit by exceeding the code. Today's fuel tank test involves a test collision and then the tested vehicle is placed on a large rotisserie and only a limited amount of fluid is allowed to leak as the crashed vehicle is rotated in space.