The U.S. Department of Transportation’s Pipeline and Hazardous Materials Safety Administration (PHMS A) has published a final rule amending its hazardous materials (HAZMAT) regulations to require a secondary means of closure for inner packaging containing a liquid HAZMAT when transported by air. 77 Fed. Reg. 22,504 (4/16/12). According to PHMS A, the requirement will help ensure that the packaging “remain[s] intact when subjected to the reduced pressure and other forces encountered in air transport.”  

Effective July 1, 2012, the rule adopts additional safety requirements for packaging containing liquids in Packing Group 1, the most dangerous classification for hazardous liquids. For those liquids, the rule also requires the presence of absorbent material and a rigid leak-proof receptacle or intermediate packaging to further mitigate the likelihood of a spill. Packaging containing liquids assigned to Packing Groups 2 or 3, which are less dangerous than those in Packing Group 1, are permitted to use a leak-proof liner or bag to meet the secondary-closure requirement.