{"data":{"id":"us/49-cfr-831.51","jurisdiction":"us","citation":"49 CFR 831.51","heading":"Definitions.","body":"The following definitions apply throughout this subpart.\nIIC means the NTSB investigator-in-charge.\nInvestigative activity means an activity performed by or under the direction of the NTSB during a casualty investigation led by the USCG.\nMajor marine casualty is defined in joint regulations of the NTSB and USCG at 49 CFR 850.5(e) and 46 CFR 4.40-5(d), respectively.\nMarine casualty means—\n(1) Any casualty, accident or event described in 46 CFR 4.03-1\n(2) An occurrence that results in an abandonment of a vessel\n(3) Other marine occurrences that the NTSB or USCG, or both, determine require investigation.","path":["Title 49—Transportation","Subtitle B—Other Regulations Relating to Transportation","CHAPTER VIII—NATIONAL TRANSPORTATION SAFETY BOARD","PART 831—INVESTIGATION PROCEDURES","Subpart E—Marine Investigations"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-49.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:34Z","sha256":"92215da958d2758c9e9ba5c7ed984b8d9f75ffb4e71d52f6b93236e08e3a2eef","source_id":"us-cfr","stale":true,"prev":"us/49-cfr-831.50","next":"us/49-cfr-831.52"},"notice":"GroundRules: Original legal text. Not legal advice."}