This notice of proposed rulemaking (NPRM) would update certain provisions of the Federal explosives regulations at 27 CFR part 555, which generally have not been updated since 1971 with the exception of some licensing and permitting amendments as a result of the Safe Explosives Act of 2002. This NPRM will be the beginning of a multiple phase process to streamline and modernize ATF’s explosives regulations to, in part, have ATF’s regulations reflect modern practices and afford regulated parties the opportunity to use information technology systems in common practice. This NPRM proposes to amend certain definitions of commonly used terms, consolidate licensing and permitting, simplify recordkeeping provisions, and clarify certain aspects of explosives storage and identification of explosive materials by multiple licensees using a single magazine.