Permit Class Submarines (SSN-594) — Asbestos in Nuclear Attack Submarine Engineering

Permit class nuclear attack submarines — thirteen hulls commissioned from 1962 through 1967 at Electric Boat (Groton), Portsmouth Naval Shipyard, Mare Island Naval Shipyard, and Ingalls Shipbuilding — were the first-generation purpose-built nuclear attack submarines designed around the tear-drop hull form pioneered by USS Albacore. Permit class submarines (USS Permit SSN-594 through USS Greenling SSN-614, plus associated hulls) were powered by the Westinghouse S5W pressurized water reactor plant — the same reactor plant used in the Skipjack class and early George Washington class — which drove a single shaft through a geared steam turbine reduction drive.

Steam Plant and Asbestos Exposure

The S5W reactor plant in Permit class submarines drove a steam turbine propulsion plant with extensive steam system insulation:

• Main steam system insulation — the high-pressure steam piping from the S5W reactor steam generators through the main propulsion turbines and ship’s service turbine generators used asbestos pipe insulation in the tight confines of the submarine engineering spaces. Machinist’s Mates performing steam system maintenance in Permit class engineering spaces worked continuously in proximity to asbestos-insulated steam piping throughout submarine operations
• Turbine insulation and lagging — the main propulsion turbines and reduction gear casings in Permit class submarines used asbestos-containing insulation blankets and lagging materials consistent with early-1960s submarine construction specifications
• Steam trap and valve insulation — the numerous steam traps and control valves throughout the submarine steam system used asbestos packing and insulation at valve bodies and in steam trap bonnets

Auxiliary Systems and Submarine Interior

Permit class submarines used asbestos-containing materials in auxiliary mechanical systems and interior construction:

• Auxiliary diesel generator — the emergency diesel generator used on Permit class submarines as backup power source used asbestos-containing exhaust system components and engine gaskets consistent with diesel auxiliary machinery of the 1960s
• Submarine interior panel insulation — the interior pressure hull lining and acoustic tile systems in Permit class submarines used asbestos-containing materials in spaces between the pressure hull and interior finishing, creating asbestos exposure during any maintenance or modification requiring access to hull structure
• Pipe insulation throughout accommodation spaces — fresh water and trim system piping throughout the accommodation compartments used asbestos-insulated piping in areas accessible to all crew members

Attack Submarine Operations

Permit class submarines served as the backbone of the Cold War attack submarine force through the 1960s and 1970s:

• Permit class submarines operated in extended submerged patrols against Soviet submarine and surface forces, with crew members living and working in close proximity to submarine engineering systems throughout each deployment
• Engineering ratings aboard Permit class submarines — Machinist’s Mates and Electrician’s Mates — routinely maintained steam plant components with asbestos-containing insulation and gasket materials throughout these extended patrols

VA Claims for Permit Class Veterans

VA evaluates asbestos-related disability claims on a case-by-case basis. Veterans generally need evidence of in-service asbestos exposure, a current asbestos-related diagnosis, and a medical link between them. Machinist’s Mates, Electrician’s Mates, and other engineering ratings who served aboard Permit class submarines and have since been diagnosed with mesothelioma, asbestosis, or asbestos-related lung cancer may qualify for VA disability benefits.

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.