US DOT Hazardous Materials Regulations (49 CFR Parts 171 to 180) 173.25-40: Overpacks, reuse and reconditioning of packagings, empty packagings, salvage packagings, and cylinder and portable tank general use (173.25, 173.28, 173.29, 173.3, 173.301 family, 173.32 family)

What does 173.25-40 require?

Overpacks must be marked with the proper shipping name and identification number and labeled as the inner packages are, with 'OVERPACK' where the inner markings are not visible. A packaging may be reused only if it is free from incompatible residue, rupture and other damage and, for specification packagings, meets the reuse conditions of 173.28 (including the leakproofness test for reused single or composite packagings for liquids and the 173.28(c) reconditioning marking). A packaging emptied of hazardous material residue is offered and transported as if full unless it meets 173.29's conditions. Damaged, defective or leaking packages may be placed in salvage packagings under 173.3. Cylinders must be qualified, filled and maintained under 173.301 to 173.306 (pressure and filling limits, requalification dates, valve protection) and portable tanks used under 173.32 and 173.33 (approvals, filling, pressure relief, tank instructions and T codes).