Product Description

According to publicly filed U.S. asbestos personal-injury and wrongful-death litigation records, Thermolyne Corporation (later Barnstead Thermolyne) allegedly manufactured, distributed, and sold bench-top laboratory muffle furnaces, tube furnaces, and crucible furnaces fitted with asbestos-refractory chamber linings, asbestos-millboard back-of-jacket insulation, and woven chrysotile asbestos-fabric door seals. Plaintiffs alleged that the chamber lining sat between the coiled resistance heating element and the sheet-metal outer jacket, and that the asbestos-fabric door seal formed the closing gasket between the swing-open door face and the front of the chamber.

Plaintiffs alleged in publicly filed litigation that Thermolyne muffle and tube furnaces were among the most common bench-top furnaces in North American academic and industrial labs from the 1950s onward, and that the asbestos components were exposed and disturbed under three routine conditions: (1) each time the door opened and closed, compressing the asbestos-fabric seal; (2) whenever the chamber lining cracked from repeated thermal cycling and required scraping, patching, or replacement; and (3) whenever a burned-out heating element required the jacket to be pulled and the asbestos-millboard insulation and refractory chamber to be disturbed to reach the element leads. Plaintiffs alleged each of those maintenance operations released respirable chrysotile fibers into the breathing zone of the lab-equipment repair technician and, secondarily, the lab worker at the bench.

Workers Exposed

Plaintiffs alleged occupational asbestos exposure from Thermolyne muffle- and tube-furnace asbestos linings and seals among the following populations:

  • Metallurgical lab technicians performing heat-treat, sinter, and diffusion work
  • Materials-testing lab operators (foundry sand, cement, ceramic firing, ash content)
  • University and college laboratory technicians in analytical, inorganic, and physical-chemistry teaching labs
  • Graduate students and postdoctoral researchers in chemistry, materials science, and geology
  • Industrial R&D lab chemists running calcination and thermal-analysis work
  • Pharmaceutical development lab chemists doing residue-on-ignition and sulfated-ash testing
  • Hospital and clinical lab technicians running specialty ashing procedures
  • Lab-equipment repair and maintenance technicians who replaced heating elements, chamber linings, and door seals