In 1922, the U.S. Navy ordered asbestos to be used in the construction of all new submarines. Chrysotile asbestos was used for gaskets, insulation, packing and tape, and amosite asbestos was specified for light-weight insulation.
Asbestos Was Heavily Used in the Construction of Submarines
The small, cramped spaces of a submarine were considered to be the perfect location in which to use asbestos. It was lightweight and flexible, easily adapting to the awkward spaces on the vessel that needed to be insulated to protect the crew from uncontrolled fires. However, the material posed an even greater injury risk than the one it was intended to prevent. Asbestos could become damaged when the submarine was attacked, as well as during the numerous overhalls a submarine required in order to be in fit condition to perform its missions. When that happened, asbestos fibers were loosened and eventually wound up in the ship’s air system, where they would be circulated throughout the vessel.
Submarine Diesel Engines Contained Asbestos
There were three classes of submarines the Navy used during World War II:
- The Gato class – Production on this class of submarine began in 1941 and continued until the availability of improved hull steel in 1944.These submarines could go to a depth of 300 feet.
- The Balao class – Production on this class began in 1943 and continued until 1944. Submarines in this class could go to a depth of 400 feet.
- The Tench class – Production on this class began in 1944 with a number of modifications on the design of the Balao class vessels. These submarines could go to a depth of 600 feet.
All of the submarines used during World War II had diesel-powered engines. The benefits of this type of engine were that it gave the submarines high speed and long range on the surface of the water. However, underwater these vessels relied on electric motors powered by storage batteries because the diesel engine was not capable of achieving the same speed and range when the submarine was submerged as it did when the vessel was on the surface.
The other drawback to this engine was that it was insulated with asbestos. The parts of the engine that contained asbestos included the exhaust pipe works, both hot and cold fluid pipes to maintain proper operating temperatures, valves, flanges and fittings.
A Remodeled Version of an Earlier Gun Becomes the Deck Gun of Choice on Submarines
A newly redesigned version of the 5”/25-caliber gun was developed as the replacement for all other weapons aboard submarines in 1944. Not only was this deck gun heavier than its predecessors, it was composed of corrosion resistant steel, making it able to withstand continuous submersion in saltwater. Its other distinguishing feature was that it could fire twenty rounds per minute. Several submarines were equipped with two of these guns.
Submarines saw a great deal of action especially in the Pacific, providing lots of opportunities to fire these huge weapons. The constant vibrations from these guns caused asbestos that was present all over the vessel to become loosened and fly into the air to be inhaled by the crew.