Signalmen — SMs — provided visual communications support for Navy ships, operating flag hoists, semaphore signals, and Aldis lamp and signal searchlight systems from the ship’s signal bridge during fleet operations and port entry. SM billets placed these personnel on the signal bridge of surface ships — the open or partially enclosed signal bridge platform on destroyers and cruisers, and the more elaborate signal bridge structure on carriers and larger surface combatants. Ships built before the mid-1970s asbestos phase-down used asbestos-containing materials in the construction of enclosed signal bridge spaces and in the mechanical systems serving the signal bridge level.

Signal Bridge Environment and Asbestos

SMs working on the signal bridge of surface ships built with asbestos construction:

  • Enclosed signal bridge interior — on carriers and larger surface combatants, the signal bridge included enclosed or partially enclosed working spaces where SMs maintained signal equipment and conducted signal watch. These enclosed signal bridge spaces on ships built before the mid-1970s used asbestos-containing materials in their interior overhead and bulkhead construction and in the heating systems serving the signal bridge level
  • Signal bridge steam heating — enclosed signal bridge spaces were heated using the ship’s steam heating system, with steam-heated radiator or fan coil units connected to asbestos-insulated steam supply piping serving the signal bridge heating circuit. SMs in the enclosed signal bridge during winter deployments were in spaces with asbestos-insulated steam heating piping in the overhead and bulkheads
  • Flag bag and equipment storage — signal flag storage lockers and equipment spaces adjacent to the signal bridge on carriers used construction materials consistent with the carrier’s overall asbestos-era construction

Carrier Signal Bridge Scale

Aircraft carrier signal bridges were larger and more complex than destroyer or cruiser signal bridges, with more personnel and more extensive enclosed spaces:

  • Carrier SMs assigned to the carrier’s flag communications department worked in signal bridge spaces integrated into the carrier’s island structure — an area of the island with asbestos in the structural steel overhead protection and in the island structure’s mechanical systems

Fleet Exercise and Deployment Watch Hours

SMs on underway surface ships stood watch rotations requiring continuous signal bridge occupancy during fleet exercises and operations:

  • Signal watch rotations during fleet exercises — where visual communication between ships was operationally frequent — placed SMs in the signal bridge environment for sustained periods throughout exercise operations

VA Claims for SM Veterans

VA presumptive service connection under 38 CFR § 3.309(d) covers asbestos exposure aboard Navy surface vessels. Signalmen who served in signal bridge billets aboard surface ships and carriers built before the mid-1970s asbestos phase-down and have since been diagnosed with mesothelioma, asbestosis, or asbestos-related lung cancer may qualify for VA disability benefits.