Ohio Class (SSBN-726) Trident Submarines — Asbestos in Ballistic Missile Submarines

The Ohio class ballistic missile submarines — 18 hulls (SSBN-726 through SSBN-743, 4 later converted to SSGN) built between 1976 and 1997 at Electric Boat (Groton, Connecticut) — replaced the aging Polaris and Poseidon SSBN fleet with a much larger vessel carrying the Trident I C-4 and later Trident II D-5 ballistic missiles. Ohio class submarines use two Westinghouse S8G nuclear reactors (one per submarine) — a natural circulation reactor design that eliminated the main coolant pumps of earlier reactor plants — generating steam through a secondary circuit for propulsion. The earliest Ohio class hulls were commissioned between 1981 and 1988, spanning the Navy’s transition from asbestos to asbestos-substitute materials in new nuclear submarine construction.

Nuclear Secondary Steam System and Asbestos

The Ohio class S8G reactor generates secondary steam for main propulsion turbines and ship’s service turbo-generators. The earliest Ohio class hulls — USS Ohio (SSBN-726) through approximately USS Pennsylvania (SSBN-735), commissioned 1981-1989 — were built during the Navy’s asbestos phase-down:

• Secondary steam piping on the earliest Ohio class hulls may retain asbestos insulation on portions of the secondary steam circuit installed before asbestos substitution was fully implemented in the construction specifications for this class
• Main propulsion turbine insulation on early hulls where turbine casing insulation was installed before the specification transition was complete
• Auxiliary steam equipment — steam traps, feedwater heaters, and auxiliary turbine connections on early hulls using asbestos-containing components under transitional specifications

Two-Crew Manning and Exposure Concentration

Ohio class submarines, like the Polaris-era SSBNs they replaced, use a two-crew (Blue/Gold) alternating manning system — maximizing deterrent patrol availability. Blue Crew and Gold Crew each conduct 70-90 day deterrent patrols aboard the same submarine, with crew rotation during a refit period. Engineering personnel aboard Ohio class submarines in the earliest hulls accumulated patrol-cycle exposure in secondary steam spaces throughout their SSBN assignments.

Trident Refit Facilities

Ohio class submarines undergo periodic maintenance at the Trident Refit Facility (TRF) at Naval Submarine Base Bangor (Washington) and TRF Kings Bay (Georgia). Maintenance at TRF involves access to secondary steam circuit components — and in the earliest Ohio class hulls, this maintenance may have involved asbestos-containing materials in the secondary steam system.

Later Ohio Class Hulls

Ohio class submarines commissioned after approximately 1989 were built under fully implemented asbestos-substitute specifications and are considered post-asbestos-phase-down in their new construction. Veterans of these later hulls’ primary exposure pathway is through prior duty aboard older nuclear submarines or surface ships.

VA Claims for Ohio Class Veterans

VA presumptive service connection under 38 CFR § 3.309(d) covers asbestos exposure aboard Navy submarines. Veterans who served in engineering billets aboard early Ohio class SSBNs (SSBN-726 through approximately SSBN-735) and have since been diagnosed with mesothelioma, asbestosis, or asbestos-related lung cancer should document all prior submarine and shipboard duty stations as part of their VA claim.

Source notes: equipment-manifest entries (where shown) are sourced from public-record BUSHIPS (Bureau of Ships) documentation, NARA archives, and the public asbestos litigation record. Manufacturer attributions link to documented asbestos-product histories on AsbestosIndex.com where available. Nothing on this page constitutes medical or legal advice.