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Coast Guard Rating · Engineering

FN Fireman

Current service use not established

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

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Overview

A Fireman stands engineering watches and cleans, paints, and preserves engineering spaces and equipment. The Fireman performs minor maintenance and repairs on engineering equipment, operates tools and test equipment, records gage readings, and reads and uses engineering drawings.

Core Skills

  • Engineering machinery maintenance assistance
  • Engineering machinery operations support

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.

Marine Oiler

FN experience assisting with machinery maintenance and operations transfers to engine-department support aboard civilian vessels.

How to prepare: Obtain an official sea-service transcript or assignment history, including vessel characteristics, assigned duties, and time underway, for Coast Guard endorsement evaluation; a DD-214 is not acceptable sea-service evidence.

What the civilian work involves
  • Read pressure and temperature gauges or displays and record data in engineering logs.
Civilian tools and software (examples)
  • Computerized maintenance management system CMMS

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 the engine-department endorsement appropriate to the intended work; the MMC authorizes only endorsed capacities and permitted lower or general capacities.

    Eligibility and preparation: Meet the requirements for each endorsement sought, including required sea service; hold a valid TWIC or have applied for one; satisfy applicable medical, vision, hearing, and physical requirements; and provide evidence of a qualifying drug test or exemption.

    For: Marine Oiler

Notes & Sources

  • The Coast Guard evaluates military sea service for merchant-vessel equivalence and the appropriate endorsement; total time aboard is not automatically credited as underway service.
Evidence for this guidance (4 documents)
  1. USCG authority snapshot: FN Fireman

    [1] data/authority/coast_guard-codes.json entry FN (Go Coast Guard - Enlisted Careers (gocoastguard.com)); fetched 2026-07-25

    Supports: Engineering machinery maintenance assistance, Engineering machinery operations support, Marine Oiler (O*NET 53-5011.00)

  2. O*NET: Sailors and Marine Oilers

    [2] O*NET 30.3 occupational data

    Supports: Marine Oiler (O*NET 53-5011.00)

  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: Marine Oiler (O*NET 53-5011.00), 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: Marine Oiler (O*NET 53-5011.00)

Defense contractor jobs for FN

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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