Asbestos gaskets sealed the joints between pipe flanges, pumps, valves, engines, boilers, and process equipment. Compressed-asbestos sheet gasket material and pre-cut asbestos gaskets were an industry standard for heat and chemical resistance and were used into the 1980s — long after asbestos was phased out of many building products.

The Biggest Clues

  • Where they are: at bolted flange joints on pipes, on pump and valve bonnets, on engine and compressor components, and on boiler and manway covers.
  • Sheet-gasket stock: rolls or sheets of stiff, paper-to-cardboard-like material (often gray, tan, or white) cut to shape on the job — a classic asbestos “compressed sheet.”
  • Appearance: thin, firm, fibrous-feeling material compressed between metal faces; sometimes with a graphite or metallic facing.
  • Age & setting: equipment, vehicles, ships, and plants from the asbestos era.

Only laboratory testing of a sample can confirm asbestos content.

Why It Is Risky

Gaskets are most dangerous during maintenance: old gaskets bake onto flanges and must be scraped, wire-brushed, or ground off, which releases fiber. Cutting new sheet gasket to shape also generated dust. Because gaskets are everywhere in industrial and vehicle equipment, mechanics and maintenance workers disturbed them constantly.

What to Do

  1. Don’t dry-scrape, grind, or wire-brush old gaskets.
  2. Test before assuming a gasket is asbestos-free on pre-1990 equipment.
  3. Use proper controls and a licensed abatement contractor where required.

Occupational Exposure

Machinists, millwrights, plumbers and pipefitters, stationary engineers, and auto mechanics who cut, installed, and scraped off asbestos gaskets were exposed throughout their careers.

If you were diagnosed with mesothelioma, asbestosis, or another asbestos-related disease and were exposed to asbestos while cutting, installing, or removing gaskets, you may have a legal claim.

This information is published by an independent media organization — not a law firm — and is educational only. It does not constitute legal advice or provide legal services.