Asbestos Manufacturing: Exposure Risks
Workers who manufactured asbestos products faced the highest exposure levels. Learn about insulation, roofing, and building material production risks.
Overview
Workers who manufactured asbestos-containing products faced the most intense and direct asbestos exposure of any occupational group. These workers handled raw asbestos fibers daily, processing them into thousands of industrial and consumer products.
Asbestos manufacturing workers handled raw asbestos fibers directly, mixing, weaving, spraying, and processing the material into finished products. This resulted in exposure levels far exceeding those in industries that merely used asbestos products.
Product Categories and Exposure Levels
Asbestos manufacturing spanned four major product categories. Each carried different fiber exposure risks based on the process.
Insulation Manufacturing
Pipe, block, and spray-on insulation drove the highest fiber exposures of any industrial process. Johns-Manville’s Kaylo pipe insulation, Owens Corning’s Kaylo (after 1958), and Unibestos (Pittsburgh Corning) used amosite asbestos mixed with calcium silicate. Workers opened bags of raw fiber, mixed it into slurries, and molded or sprayed the finished blocks.
| Product | Manufacturing Process | Exposure Level |
|---|---|---|
| Pipe insulation (Kaylo, Unibestos) | Amosite mixed with calcium silicate, molded into pre-formed sections | Extreme |
| Block insulation | Molding asbestos-calcium mixtures for boilers and turbines | Extreme |
| Spray-on insulation (Limpet, Monokote) | Mixing loose fiber with binders, pneumatic spray application | Extreme |
| Insulation blankets and felts | Weaving asbestos cloth, filling jackets with loose fiber | Very High |
Building Materials, Friction Parts, and Textiles
Beyond insulation, three other product lines ran through asbestos plants for decades.
Building materials included Portland cement mixed with chrysotile for Transite boards, siding, and pipe. GAF, Celotex, and Flintkote pressed asbestos into roofing felt and shingles. Floor tile manufacturers mixed chrysotile with vinyl resins, and ceiling tile lines used asbestos as fireproofing through the 1970s.
Friction products were made by Raybestos-Manhattan, Bendix, and similar operators. Workers wove and pressed chrysotile into brake linings, clutch facings, and heavy-duty industrial brakes. Grinding and cutting finished parts released visible fiber into the air.
Textile operations spun asbestos yarn and thread, wove fire-resistant blankets and curtains, and stitched protective clothing for foundry and glass workers. Garlock and similar manufacturers pressed woven asbestos into gaskets and pump packing.
Manufacturing Jobs at Risk
Raw material handlers opened bags of crude asbestos and dumped them into mixers. Mixers and machine operators ran the production equipment. Quality control staff tested finished products on open benches. Maintenance workers cleaned fiber-caked equipment and replaced worn asbestos-lined machinery, and warehouse workers handled packaged products that shed fiber during loading.
Major Asbestos Manufacturers
The companies that dominated US asbestos production included Johns-Manville, Owens Corning, W.R. Grace, GAF Corporation, Celotex, Eagle-Picher Industries, Raybestos-Manhattan, Pittsburgh Corning (Unibestos), Flintkote Company, and Garlock. Most later filed for bankruptcy and established trusts under Section 524(g) of the Bankruptcy Code.
Many major asbestos manufacturers filed for bankruptcy due to asbestos litigation. As a result, they established trust funds to compensate affected workers and families. Over $30 billion has been set aside in these trusts.
Family Exposure
Manufacturing workers unknowingly carried asbestos fibers home on their clothing, hair, and skin, exposing family members to secondary asbestos exposure. Many spouses and children of asbestos manufacturing workers have developed mesothelioma.
Legal Options
Workers diagnosed with mesothelioma or asbestos-related cancer may pursue compensation through asbestos trust funds (most major manufacturers have established trusts totaling more than $30 billion), personal injury claims against companies still solvent, workers’ compensation through employer coverage, and Social Security disability for qualifying conditions.