Steel Mills and Shipyards: Pennsylvania Asbestos Exposure Legacy

Pennsylvania’s position as the state with the second highest per capita mesothelioma rate in the country traces to two industrial corridors that defined the state’s economy for more than a century: the steel mills of the Lehigh Valley and western Pennsylvania, and the shipbuilding operations along the Delaware River.

The workers who poured the steel, built the ships, and maintained the machinery are the ones receiving diagnoses now, decades after the furnaces cooled and the shipyards closed. Their exposure was not incidental. It was embedded in every shift.

The Steel Corridor

Bethlehem Steel

Bethlehem Steel’s complex in the Lehigh Valley was among the most significant industrial operations in American history. At its peak, the company employed more than 30,000 workers at its Pennsylvania facilities. The plant produced structural steel, armor plate, and forgings for everything from bridges to battleships.

Asbestos was integral to steelmaking. Blast furnaces and open-hearth furnaces operated at extreme temperatures, and asbestos insulation lined the structures, pipes, and equipment surrounding them. Workers who maintained the insulation stripped and replaced asbestos-containing materials as part of routine operations. Rolling mills, the massive machines that shaped molten steel into beams, plates, and rails, used asbestos brake pads, gaskets, and insulation, and millwrights and maintenance crews serviced this equipment daily.

Pipe systems added another exposure pathway. Steam lines, hydraulic systems, and cooling water pipes throughout the complex were insulated with asbestos, and pipefitters cut, fit, and replaced this insulation for decades. Fireproofing finished the picture: asbestos-containing fireproofing materials were applied to structural steel, walls, and ceilings across the facility.

Pittsburgh Steel Mills

The steel corridor along the Monongahela and Ohio rivers contained dozens of mills operated by U.S. Steel, Jones & Laughlin, and other producers. The exposure profile mirrored Bethlehem Steel: furnace insulation, pipe covering, gaskets, brake systems, and fireproofing. Pittsburgh’s steel belt was part of a larger industrial corridor that stretched west through Cleveland’s Rust Belt mills, Gary, Indiana, and into Chicago’s Southeast Side, all of which used the same asbestos insulation products from the same manufacturers.

Workers at Pittsburgh-area mills faced the same concentrated exposure as their Lehigh Valley counterparts. The combination of extreme heat, enclosed working environments, and decades-long careers created conditions for heavy asbestos fiber inhalation.

The Philadelphia Navy Yard

The Philadelphia Naval Shipyard was the largest naval shipbuilding facility on the East Coast and one of the busiest in the country. During World War II, the yard employed more than 40,000 workers building and repairing destroyers, aircraft carriers, and other warships.

Shipyard workers faced some of the most concentrated asbestos exposure of any occupation. Asbestos was used throughout every vessel.

Pipe insulation ran through every ship. Naval vessels contained miles of piping for steam, water, and fuel, and every pipe was insulated with asbestos-containing material. Laggers and pipefitters installed and replaced this insulation in confined spaces throughout the hull. Boiler rooms were the most concentrated exposure zones. Boilers and their associated systems were heavily insulated with asbestos, and boilermakers who worked on them inhaled fibers during installation, maintenance, and repair.

Fireproofing and gaskets spread the exposure across trades. Asbestos was sprayed on bulkheads, decks, and structural members as fireproofing, exposing workers in adjacent areas during application and whenever the material was disturbed. Valves, pumps, and flanges throughout the ship used asbestos gaskets, and mechanics replaced these components regularly, releasing fibers with each repair.

Below-deck work in enclosed compartments created particularly concentrated exposure. Ventilation was limited, and multiple trades often worked in the same confined space, generating cumulative airborne fiber levels that far exceeded what would later be recognized as safe limits. The same below-deck conditions existed at the Brooklyn Navy Yard, Jacksonville’s naval shipyards, and Savannah’s shipbuilding operations, where East Coast Navy workers faced identical hazards.

Manufacturing and Construction

Beyond steel and shipbuilding, Pennsylvania’s manufacturing sector created thousands of additional exposure points. Oil refineries along the Delaware River and in Butler County used asbestos in piping, insulation, and process equipment. Beaver County’s chemical plants used asbestos in reactor vessels, pipe systems, and fireproofing. Coal-fired power stations across the state used asbestos in boilers, turbines, and steam distribution systems. And pre-1980 commercial and public buildings throughout the state were constructed with asbestos-containing insulation, floor tiles, roofing, and fireproofing.

Take-Home Exposure

Pennsylvania’s industrial workers carried asbestos fibers home on their clothing. Spouses who laundered work clothes and children who greeted their parents at the door were exposed to the same material accumulating in workers’ lungs.

Pennsylvania courts have recognized take-home exposure as a valid basis for claims. The Virginia Supreme Court’s 2026 ruling that shipyard employers owed a duty of care to workers’ families reinforced the legal foundation for these claims across the mid-Atlantic. Families affected by secondhand exposure may have both lawsuit and trust fund options.

For legal outcomes from cases involving these exposure sites, see verdicts and settlements.