Thermoid Brand Asbestos Woven Cloth and Tape (H.K. Porter Company)

Thermoid brand asbestos woven cloth and tape were industrial textile products manufactured by H.K. Porter Company and widely distributed throughout American industry for much of the twentieth century. Workers who handled, installed, or worked near these products may have sustained asbestos exposure and may be eligible to file a claim with the H.K. Porter Company Asbestos Settlement Trust.

Product Description

H.K. Porter Company was a diversified industrial manufacturer headquartered in Pittsburgh, Pennsylvania, with product lines spanning tools, metals, and specialty industrial materials. Among its manufactured goods, H.K. Porter produced a line of asbestos textile products marketed under the Thermoid brand name. These products included woven asbestos cloth and asbestos tape, both of which were engineered for applications demanding resistance to high heat, flame, and mechanical abrasion.

Asbestos woven cloth was produced in sheets or rolls of varying widths and thicknesses, formed by weaving asbestos fiber yarn on industrial looms into a durable fabric. Asbestos tape was produced in a similar manner but cut or woven into narrower strips intended for wrapping, binding, and sealing applications. Both products could be supplied in plain woven form or combined with wire reinforcement to enhance structural integrity under mechanical stress.

Thermoid asbestos cloth and tape found application across a broad range of industrial settings. These products were used to fabricate heat shields, pipe insulation overwrap, equipment covers, gaskets, and packing materials. In industrial plants and manufacturing facilities, the cloth was commonly draped or stitched around hot surfaces, valves, and piping systems. The tape served as a wrapping material for pipe joints, flanges, and mechanical components where thermal insulation and fire resistance were required. The Thermoid name was associated with quality in the industrial textile market, and these products were sold through industrial supply distributors to facilities across the United States.

Asbestos Content

Asbestos woven cloth and tape were products whose utility was derived directly from the physical properties of asbestos fiber. Asbestos fiber — most commonly chrysotile, and in some formulations amphibole varieties such as amosite or crocidolite — was spun into yarn and woven into cloth using conventional textile manufacturing techniques adapted for asbestos fiber. The finished cloth and tape were composed predominantly of asbestos fiber, with some formulations incorporating wire, cotton, or other fiber blends to achieve specific performance or handling characteristics.

Because asbestos was the primary structural and functional component of these textile products, asbestos fiber content was high by design. The woven structure of the cloth and tape held asbestos fibers in a loosely bound matrix that could release fibers during handling, cutting, tearing, or abrasion. Trust fund documentation and litigation records confirm that Thermoid brand asbestos textile products manufactured by H.K. Porter Company contained asbestos as a principal ingredient.

How Workers Were Exposed

Industrial workers across a wide range of trades and facilities encountered Thermoid asbestos woven cloth and tape throughout the product’s period of manufacture and use. Exposure occurred at multiple points in the product lifecycle, from initial fabrication and installation through routine maintenance and ultimate removal.

Workers who cut asbestos cloth to size for fabrication of heat shields, covers, or custom gaskets generated visible dust and airborne fiber during the cutting process. Sawing, shearing, or trimming the woven material caused asbestos fibers to break free from the woven matrix and become suspended in workplace air. Workers performing this fabrication work, as well as those in the immediate vicinity, were subject to inhalation exposure.

Installation of asbestos tape involved hand wrapping of pipe fittings, flanges, valve stems, and mechanical components. The process of unrolling, tearing, and pressing the tape against surfaces disturbed asbestos fibers and released dust. Workers in boiler rooms, engine rooms, industrial plants, power generation facilities, refineries, and manufacturing operations regularly performed this type of work as part of routine maintenance and new construction activities.

Maintenance and repair activities presented ongoing exposure opportunities over the working life of these materials. As asbestos cloth and tape aged, it became brittle and friable, meaning that minor physical contact was sufficient to release fiber into the air. Workers removing old tape or cloth to access underlying equipment, or performing repairs in proximity to deteriorated asbestos textile materials, sustained exposure even when the primary task did not directly involve the asbestos product itself.

Pipe fitters, boilermakers, millwrights, insulators, maintenance mechanics, and general industrial laborers are among the occupational groups documented in trust fund and litigation records as having worked with or around asbestos textile products of this type. Facilities including steel mills, chemical plants, paper mills, automotive manufacturing plants, and similar heavy industrial environments were settings where Thermoid asbestos cloth and tape were commonly used.

Inhalation of asbestos fiber is the established pathway for development of asbestos-related diseases. Diseases associated with occupational asbestos exposure include mesothelioma, asbestosis, asbestos-related lung cancer, and pleural disease. These conditions typically have latency periods of ten to fifty years between initial exposure and clinical diagnosis.

The H.K. Porter Company Asbestos Settlement Trust was established to compensate individuals harmed by asbestos-containing products manufactured and distributed by H.K. Porter Company, including Thermoid brand asbestos woven cloth and tape. The trust was created as part of the resolution of H.K. Porter Company’s asbestos liability, providing a dedicated fund for eligible claimants without requiring active litigation against the company.

Individuals diagnosed with an asbestos-related disease who can document exposure to Thermoid brand asbestos cloth or tape manufactured by H.K. Porter Company may be eligible to submit a claim to the trust. Eligible disease categories typically include:

  • Mesothelioma (malignant mesothelioma of the pleura, peritoneum, or pericardium)
  • Lung cancer with documented asbestos exposure
  • Asbestosis meeting applicable medical criteria
  • Other asbestos-related pleural disease meeting trust eligibility requirements

Claims are evaluated based on medical documentation of diagnosis, evidence of exposure to a covered H.K. Porter product, and compliance with applicable trust distribution procedures (TDPs). Exposure documentation may include employment records, union records, co-worker testimony, Social Security work history, and product identification records.

Surviving family members filing on behalf of deceased individuals with a qualifying diagnosis may also have standing to submit claims, subject to the trust’s procedures for wrongful death and estate claims.

Individuals who believe they may have been exposed to Thermoid asbestos woven cloth or tape manufactured by H.K. Porter Company should consult with an attorney experienced in asbestos trust fund claims. Time limitations apply to the filing of asbestos claims, and prompt action following a diagnosis is advisable to preserve eligibility and documentation.