Office of Marine Safety

​​​​​​​Program Description

​The Office of Marine Safety (OMS) investigates marine casualties to determine the probable cause of each casualty and identify safety recommendations that will prevent similar events in the future. Investigated casualties include those classified by the US Coast Guard as major marine casualties in US territorial waters or involving US flagged vessels worldwide, and casualties involving both US public (government) and nonpublic vessels. In addition, the office investigates select catastrophic marine casualties, as well as those of a recurring nature.

These responsibilities are specified in the Independent Safety Board Act and Title 49 Code of Federal Regulations Part 850. Major marine casualties may include any one of the following:

  • the loss of six or more lives.
  • the loss of a mechanically propelled vessel of 100 or more gross tons.
  • property damage initially estimated to be $500,000 or more.
  • a serious threat, as determined by the Commandant of the Coast Guard with the concurrence of the NTSB Chair, to life, property, or the environment by hazardous materials.

​After investigating each major marine casualty, the OMS identifies safety issues and issues an investigation report, which may include safety recommendations to federal government agencies (such as the Coast Guard), state agencies, vessel owners and operators, vessel classification societies, or maritime industry organizations.

Under the International Maritime Organization’s (IMO) Casualty Investigation Code, the OMS also participates with the Coast Guard as a Substantially interested S​tate in investigations of serious marine casualties involving foreign-flagged vessels in international waters. For example, the NTSB often participates in casualty investigations that involve foreign-flagged cruise ships with US citizens on board.

​OMS also actively participates in US-based and international groups to improve marine investigations and promote maritime safety. This includes:

  • ​reviewing US position papers related to marine casualty investigations,
  • participating in International Maritime Organization meetings, 
  • staying abreast of the latest advancements, techniques, and technologies in marine casualty investigation and prevention, and
  • collaborating with other marine casualty investigation organizations worldwide on investigations and other investigative activities aimed at improving safety. ​



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