Merchant Mariners Lived Inside the Asbestos

For most of the twentieth century, the ships that moved America’s cargo, fuel, and troops were insulated with asbestos from the bilge to the boat deck. Cargo vessels, tankers, and troop transports were built the same way warships were — miles of steam pipe wrapped in asbestos lagging, boilers packed in asbestos block and cement, turbines and pumps sealed with asbestos gaskets and packing, and bulkheads and overheads lined with asbestos for fireproofing. A merchant mariner did not visit that environment for a watch and leave. He lived in it, often for months at a stretch, sleeping and eating aboard a steel hull where asbestos dust had nowhere to go.

Merchant mariners were also uniquely unprotected. Unlike a shoreside plant with ventilation and (eventually) exposure limits, a ship at sea is a sealed box. When lagging was disturbed for a repair — and at sea, repairs happen constantly — the dust circulated through the same passageways, mess decks, and berthing spaces where the crew lived.

Where the Exposure Happened

Exposure tracked closely to a mariner’s department and rating:

  • Engine department — the heaviest exposure. Oilers, firemen/watertenders, wipers, QMEDs, and licensed engineers worked directly among asbestos-lagged boilers, steam lines, turbines, evaporators, and pumps. Removing and rebuilding insulation to service machinery was routine engine-room work. See Engine Room & Boiler Room Exposure.
  • Deck department — able seamen, ordinary seamen, and bosuns handled cargo, rigging, and maintenance that ran through asbestos-insulated spaces, king posts, and deck machinery.
  • Steward department — cooks and stewards worked in galleys where ovens, ranges, and the piping behind them were commonly asbestos-insulated.

The WWII Liberty & Victory Generation

The single largest exposed population came out of World War II. The United States mass-produced roughly 2,700 Liberty ships and some 500 Victory ships, built fast and packed with asbestos insulation, and crewed them with merchant mariners who suffered one of the highest casualty rates of any American service in the war. That same generation went on to decades of civilian sea service on ships built to the same asbestos standard. See Liberty & Victory Ship Asbestos Exposure.

Military Sealift — The Navy Connection

Merchant mariners have long crewed the government-owned ships that keep the fleet supplied — first under the Military Sea Transportation Service (MSTS) and, from 1970, Military Sealift Command (MSC). Civilian mariners aboard these ships worked the same asbestos-laden engineering plants as their Navy counterparts. It is one reason merchant-marine and Navy asbestos histories run in parallel — and why WWII merchant mariners were granted veteran status in 1988, making some eligible for a discharge record and limited VA benefits alongside a civil claim.

Maritime law gives seamen distinct doctrines — the Jones Act (Merchant Marine Act of 1920) and the general-maritime rule of “unseaworthiness” — explained as background on the page below. Separately, and like other exposed workers, a mariner may have a civil claim against the companies that allegedly manufactured or supplied the asbestos materials used aboard, and against the asbestos trusts they established. That civil product claim is the focus of an experienced asbestos attorney. See Jones Act & Merchant Mariner Asbestos — Legal Background.

Merchant mariners came up through unions that still hold retiree and reunion networks — the SIU, MEBA, AMO, and MM&P among them. See Merchant Marine Unions & Asbestos.