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Navy NEC · Engineering

B18A Master Underwater Construction Diver

Current service use not established

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

A Navy Enlisted Classification: a skill designation sailors hold in addition to their rating.

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Overview

The Master Underwater Construction Diver supervises air and mixed gas dives using SCUBA and surface supplied equipment and ensures the safe conduct of diving operations. This diver manages diving and construction equipment, trains personnel, oversees certification and quality assurance programs, and supports underwater construction, inspection, demolition, and recompression therapy.

Core Skills

  • Mixed-gas analysis and diver gas calculations
  • Underwater construction, inspection and demolition
  • Diving system certification and quality assurance
  • Recompression chamber and support system operation

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.

Commercial Divers

Your experience supervising air and mixed-gas dives, performing underwater construction and inspection, and managing diving-equipment maintenance directly overlaps commercial diving work.

How to prepare: Have a prospective employer assess your existing Navy qualifications, training records and dive logs against the assigned diving mode and OSHA dive-team requirements before selecting gap training. If seeking ADCI classification, request an equivalency review: its Entry Level framework requires 625 documented instructional hours or a recognized equivalent, while Air Diver requires at least 100 field days and 30 working dives, with only surface-supplied dives counting toward Air Diver requirements.

What the civilian work involves
  • Take appropriate safety precautions, such as monitoring dive lengths and depths and registering with authorities before diving expeditions begin.
  • Check and maintain diving equipment, such as helmets, masks, air tanks, harnesses, or gauges.
  • Obtain information about diving tasks and environmental conditions.
Civilian tools and software (examples)
  • Diving logbook software
  • Diving table software

Notes & Sources

  • For work covered by OSHA commercial-diving rules, dive-team members need task-appropriate experience or training, CPR and first-aid training, and diving physics and physiology training when exposed to or controlling hyperbaric exposure.
  • OSHA prohibits diving or other hyperbaric exposure during a known temporary physical impairment or condition likely to compromise safety or health.
  • ADCI classifications are an industry certification framework, not a universal government diving license.
Evidence for this guidance (4 documents)
  1. NAVPERS 18068F Vol II (NEOCS, Jul 2026 edition): NEC B18A

    [1] NEC entry "B18A - Master Underwater Construction Diver"; cached text line 2334; NAVPERS 18068F Vol II, 2026-07 edition

    Supports: Mixed-gas analysis and diver gas calculations, Underwater construction, inspection and demolition, Diving system certification and quality assurance, Recompression chamber and support system operation, Commercial Divers (O*NET 49-9092.00)

  2. O*NET: Commercial Divers

    [2] O*NET 30.3 occupational data

    Supports: Commercial Divers (O*NET 49-9092.00)

  3. OSHA 29 CFR 1910.410: Qualifications of dive team

    [3] Commercial Diving Operations, paragraphs (a) and (b). Verified 2026-09-24.

    Supports: Commercial Divers (O*NET 49-9092.00)

  4. ADCI: Commercial diver classification requirements

    [4] Entry Level and Air Diver card classifications. ADCI framework, not a universal government license. Verified 2026-09-24.

    Supports: Commercial Divers (O*NET 49-9092.00)

Defense contractor jobs for B18A

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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