On March 30, 2017 (82 FR 15796) the Pipeline and Hazardous Materials Safety Administration (PHMSA), issued a final rule to amend the Hazardous Materials Regulations (HMR) to maintain consistency with international regulations and standards by incorporating various amendments, including changes to proper shipping names, hazard classes, packing groups, special provisions, packaging authorizations, air transport quantity limitations, and vessel stowage requirements. These revisions are necessary to harmonize the HMR with recent changes made to the International Maritime Dangerous Goods Code, the International Civil Aviation Organization's Technical Instructions for the Safe Transport of Dangerous Goods by Air, and the United Nations Recommendations on the Transport of Dangerous Goods—Model Regulations. Additionally, PHMSA is adopting several amendments to the HMR that result from coordination with Canada under the U.S.-Canada Regulatory Cooperation Council. This rule is effective March 30, 2017, except for instruction 22, which is effective January 2, 2019. Voluntary compliance date was January 1, 2017. Unless otherwise specified, compliance with the amendments adopted in this final rule is required beginning January 1, 2018 (delayed compliance date). Incorporation by reference date: The incorporation by reference of certain publications listed in this rule is approved by the Director of the Federal Register as of March 30, 2017.