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Coast Guard Officer specialty · Support

BOSN Boatswain

Current service use not established

This code is listed in the directory. Inclusion alone does not confirm current service use.

A Coast Guard officer specialty, not an enlisted rating.

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Overview

A Boatswain serves as a technical expert for the deck department, leads operations, advises commissioned officers, and makes management decisions. The officer manages personnel records and training programs, acts as a liaison between executive management and lower-level personnel, and may command a Coast Guard vessel, unit, or station.

Core Skills

  • Technical guidance on vessel handling
  • Navigation and deck operations expertise

Civilian Career Paths

Career associations are editorial assessments of the cited evidence, not an official crosswalk unless the evidence explicitly says so. O*NET supplies civilian occupation information, not proof of a military match. Related experience does not confer civilian qualifications. Tasks and tools below describe civilian work, not military training.

Captains, Mates, and Pilots of Water Vessels

BOSN technical authority in vessel handling, navigation, and deck operations directly overlaps civilian vessel navigation and operation.

How to prepare: Request an official sea-service transcript or assignment history, with vessel tonnage, routes, propulsion power, time underway, and assigned duties, for Coast Guard endorsement evaluation; a DD-214 is not acceptable sea-service evidence. A Master unlimited endorsement based on military service requires service as a commanding officer.

What the civilian work involves
  • Direct courses and speeds of ships, based on specialized knowledge of local winds, weather, water depths, tides, currents, and hazards.
  • Consult maps, charts, weather reports, or navigation equipment to determine and direct ship movements.
  • Steer and operate vessels, using radios, depth finders, radars, lights, buoys, or lighthouses.

Bridge and Lock Tenders

BOSN vessel-handling and navigation expertise transfers to assessing vessel approaches and coordinating passage through confined waterways.

How to prepare: Seek supervised familiarization with a bridge or lock operator's machinery controls and vessel-passage signaling procedures.

What the civilian work involves
  • Direct movements of vessels in locks or bridge areas, using signals, telecommunication equipment, or loudspeakers.
  • Observe position and progress of vessels to ensure best use of lock spaces or bridge opening spaces.
  • Observe approaching vessels to determine size and speed, and listen for whistle signals indicating desire to pass.

Training & Development

Choose credentials for your target role. COOL funding markers describe program listings, not a guarantee of eligibility or funding.

Getting Started

  • USCG Merchant Mariner Credential

    Obtain authorization to serve in the civilian deck capacities covered by the credential's endorsements.

    Eligibility and preparation: Meet the requirements for each endorsement sought, including required documented sea service and applicable medical, vision, hearing, and physical standards; provide proof of a valid TWIC or a TWIC application and a qualifying drug test or exemption.

    For: Captains, Mates, and Pilots of Water Vessels

Notes & Sources

  • The Coast Guard evaluates military sea service for merchant-vessel equivalence and endorsement grade, class, and limits; normally 60 percent of total time onboard counts as equivalent underway service, though vessel operating periods may be evaluated separately.
Evidence for this guidance (5 documents)
  1. USCG authority snapshot: BOSN Boatswain

    [1] data/authority/coast_guard-codes.json entry BOSN (COOL USCG MOC Feed (uscg.json) + COOL Feed (uscg.json) + CG COOL Website); fetched 2026-07-25

    Supports: Technical guidance on vessel handling, Navigation and deck operations expertise, Captains, Mates, and Pilots of Water Vessels (O*NET 53-5021.00), Bridge and Lock Tenders (O*NET 53-6011.00)

  2. O*NET: Captains, Mates, and Pilots of Water Vessels

    [2] O*NET 30.3 occupational data

    Supports: Captains, Mates, and Pilots of Water Vessels (O*NET 53-5021.00)

  3. eCFR: 46 CFR part 10 - Merchant Mariner Credential issuance requirements

    [3] 46 CFR 10.201, 10.209 and 10.225; official eCFR XML API as of 22 September 2026

    Supports: Captains, Mates, and Pilots of Water Vessels (O*NET 53-5021.00), USCG Merchant Mariner Credential

  4. USCG: 46 CFR 10.232 military sea-service evidence and credit

    [4] Paragraphs (a) and (d)(1), official eCFR snapshot September 21, 2026; retrieved September 24

    Supports: Captains, Mates, and Pilots of Water Vessels (O*NET 53-5021.00)

  5. O*NET: Bridge and Lock Tenders

    [5] O*NET 30.3 occupational data

    Supports: Bridge and Lock Tenders (O*NET 53-6011.00)

Defense contractor jobs for BOSN

Descriptions may be summarized for clarity. Verify all information with your branch career counselor or official military documentation before making career decisions.

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