Gaskets and Asbestos Exposure

Summary

For most of the twentieth century, asbestos gaskets were out of sight and out of mind. However, gaskets played an enormously important role in so many mechanical applications. They allowed imperfect metal surfaces to mate and seal. Gaskets compressed when tightened and maintained high pressures in contained areas while prohibiting the transfer of liquids and chemicals. They also needed to withstand high heat while staying stable for extended periods.

At one time, asbestos was the prime choice for gasket material.

Gaskets were essential components in the mechanized industrial world. Almost every piece of machinery and delivery infrastructure used gaskets for joints and seals. Asbestos was often blended with other materials to form gasket compounds, and the range of asbestos content could be anywhere from as low as 5 percent to nearly pure.

Asbestos was considered the perfect gasket material for every application. Asbestos was inexpensive, readily available and stable. It was fireproof and could withstand extreme heat making it the ideal thermal isolation material. As well, asbestos gaskets were non-corrosive, impervious to chemical reactions and non-conductive of electricity.

Asbestos gasket material was also easy to cut, shape, form and blend with other materials like metal and cement. Although many gaskets were formed in factories, often workers made gaskets on site. This process was common in specialized situations where commercial, ready-made gaskets were unavailable. Asbestos was such a useful material and appeared to be user-friendly and completely safe at the time.

Asbestos Gasket Applications

Every mechanical component joint used gasket materials. In low-pressure and minimal heat applications, sealants like grease or cloth were common. But when temperatures climbed and pressures increased, a hardier gasket substance was needed.

Numerous mechanical workers turned to asbestos for gaskets and used it for:

  • Gasoline and diesel engines: Asbestos head gaskets were exclusively used to seal combustion chambers and control coolant pressures.
  • Furnaces and boilers: Extreme heat and combustible materials were contained by asbestos gaskets.
  • Shipbuilding flanges: Ships required large gaskets to seal flanges where water control was an issue. Asbestos was impervious to corrosion from salt water.
  • Chemical plants: Chemical-producing factories used asbestos gaskets where reaction risks were present. Asbestos was chemically inert and wouldn’t react to other materials.
  • Electrical generating stations: High voltages were ever-present, and asbestos gaskets in generators insulated components from shorts and groundings.

Different gasket applications required combining asbestos materials into a menagerie of shapes and sizes. Creative inventors formed asbestos in rope gaskets, spiral-wound gaskets and oval gaskets. But the most common asbestos gasket material was large sheet stocks that were hand-cut and manufactured right on the job site. This exposed workers to large amounts of airborne asbestos fibers which proved deadly to their health.

Types of Asbestos Used in Gaskets

Chrysotile asbestos was by far the most common asbestos material used in making gaskets. Chrysotile is also called white asbestos, and it falls in the serpentine asbestos classification. When an individual is looking under a microscope, chrysotile asbestos fibers appear serpent-shaped with soft edges.

The lesser-common asbestos class used in gasket making was amphibole asbestos. It appears as a crystal with numerous sharp spikes. There are five different forms of amphibole asbestos with amosite asbestos being the main sub-class used in gaskets. Amosite was used in high heat and corrosive situations. Amphibole asbestos exposure is much more dangerous than chrysotile fibers, but that doesn’t make chrysotile gasket materials safe.

MJN Brief

The Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) had asbestos gaskets banned in the 1980s. However, by then hundreds of millions of asbestos gaskets were installed in every conceivable application across America. Many are still in use today and expose unsuspecting workers to asbestos fibers when removing and replacing old, worn out asbestos gaskets.

 

Asbestos Gaskets and Mesothelioma

Mesothelioma is a fatal form of lung cancer. Its sole cause is exposure to asbestos fibers. That includes both chrysotile and amphibole asbestos particles. Asbestos fibers became airborne in factory manufacturing plants and at on-site repair locations. Unprotected workers inhaled these tiny particles that attached to workers’ lung lining which is called the mesothelium.

Once embedded in the mesothelium, asbestos fibers don’t release. They stay in the mesothelium forever and eventually build scar tissue. There is an extended latency period, but this mass turns tumorous and becomes the deadly disease called mesothelioma.

Compensation for Mesothelioma Victims

Although advanced mesothelioma is incurable, victims can receive financial compensation. Awards are available to compensate personal injury damages, lost income and medical costs. Families of mesothelioma victims can sue negligent asbestos material manufacturers and suppliers on their behalf. They can also file lawsuits in wrongful death cases.