CM-18 Gun Mix

Product Description

CM-18 Gun Mix was a spray-applied refractory and insulating material manufactured by Narco (National Refractories and Minerals Corporation) and produced from approximately 1963 through 1977. The product was designed for use in high-temperature industrial environments, where it was applied via pneumatic spray equipment — commonly called a “gun” application method — to pipe insulation, boiler components, furnace linings, and other industrial infrastructure requiring thermal protection.

Narco marketed CM-18 Gun Mix to a broad range of heavy industrial operations, including steel mills, refineries, chemical processing plants, and power generation facilities. The gun-application method made the product well-suited for covering irregular surfaces and hard-to-reach areas of pipe systems and equipment enclosures, allowing workers to apply a uniform insulating coat with relative speed compared to hand-applied alternatives. The material was engineered to withstand sustained elevated temperatures and to provide thermal efficiency in demanding process environments.

Production of CM-18 Gun Mix continued for roughly fourteen years, placing it squarely within the period — the 1960s and 1970s — when asbestos use in commercial and industrial insulation products was at or near its historical peak. Regulatory scrutiny of asbestos in workplace products intensified following this era, and the product was discontinued before the end of the 1970s.

Asbestos Content

CM-18 Gun Mix contained chrysotile asbestos as a component of its formulated mix. Chrysotile, sometimes referred to as “white asbestos,” is a serpentine mineral fiber that was widely incorporated into refractory, insulating, and construction materials throughout the mid-twentieth century because of its heat resistance, tensile strength, and binding properties.

Although chrysotile has a different fiber morphology from amphibole varieties such as amosite or crocidolite, regulatory agencies and health authorities — including the U.S. Environmental Protection Agency (EPA) under the Asbestos Hazard Emergency Response Act (AHERA) and the Occupational Safety and Health Administration (OSHA) — classify all forms of asbestos as hazardous. OSHA’s permissible exposure limit (PEL) for asbestos, established and refined through successive rulemaking, applies to chrysotile without distinction from other asbestos fiber types.

In spray-applied products such as CM-18 Gun Mix, chrysotile fibers were integrated into the mix to enhance thermal stability and structural integrity of the finished coat. The practical consequence of this formulation was that significant quantities of respirable asbestos fiber were present in the dry product and could be released at multiple stages of the product’s life cycle — during manufacturing, mixing, application, and subsequent disturbance or removal.

How Workers Were Exposed

Industrial workers employed in facilities that used CM-18 Gun Mix faced potential asbestos exposure through several distinct pathways, each associated with different tasks and phases of the product’s use.

Mixing and loading operations represented a primary exposure pathway. Before the gun-application process could begin, workers or helpers prepared the dry mix, combining CM-18 Gun Mix powder with water to achieve the proper consistency for spray application. Opening bags of dry material, pouring the contents, and agitating the mix released chrysotile dust directly into the breathing zone of workers performing these tasks.

Gun application itself created airborne fiber concentrations in the immediate work area and in adjacent spaces. Spray application of asbestos-containing materials generates a plume of particulate that disperses beyond the spray zone. Workers operating the spray gun, those handling hoses and equipment, and workers in the surrounding area — including other trades present in the same industrial space — could inhale fibers that remained suspended in the air.

Maintenance, repair, and removal activities posed significant long-term exposure risks. Pipe insulation and refractory coatings applied with CM-18 Gun Mix were subject to mechanical damage, thermal cycling, and normal industrial wear. When workers chipped, ground, or removed deteriorated insulation from pipes and equipment, the hardened material fractured and released embedded chrysotile fibers. These secondary disturbance exposures could occur years or decades after the original application, meaning that workers in industrial maintenance roles were at risk long after the product itself had been discontinued.

Litigation records document that industrial workers across a range of job categories encountered CM-18 Gun Mix during its production years and in subsequent decades as installed insulation aged and required attention. Plaintiffs alleged that they were exposed during the course of ordinary industrial work, including pipe fitting, boilermaking, millwright operations, and general maintenance in facilities where the product had been applied. Plaintiffs further alleged that neither adequate warnings of the health hazards associated with asbestos inhalation nor sufficient respiratory protection were provided to workers during the years when CM-18 Gun Mix was in active use.

The latency characteristics of asbestos-related disease — mesothelioma, asbestosis, and lung cancer may not manifest clinically for twenty to fifty years following initial exposure — mean that workers exposed to CM-18 Gun Mix during the 1960s and 1970s may only now be receiving diagnoses linked to those historic exposures.

CM-18 Gun Mix is a Tier 2 — Litigated product. No dedicated asbestos bankruptcy trust fund has been established for Narco specifically in connection with this product in the manner that exists for some other asbestos manufacturers. Claims arising from exposure to CM-18 Gun Mix have proceeded through the civil litigation system rather than through a structured trust fund claims process.

Litigation records document that individuals who developed asbestos-related illnesses and alleged exposure to Narco’s CM-18 Gun Mix, or to Narco products generally, have brought civil actions in state and federal courts. Plaintiffs alleged that Narco knew or should have known of the hazards associated with chrysotile asbestos in its gun mix formulations and failed to adequately warn end users, contractors, and industrial workers of those risks.

For individuals who believe they were exposed to CM-18 Gun Mix and have received a diagnosis of an asbestos-related disease, the following steps are relevant:

  • Consult a qualified asbestos attorney. Legal professionals specializing in asbestos litigation can evaluate the specific facts of a claim, identify all potentially liable parties, and determine the appropriate legal venue.
  • Document exposure history. Employment records, union records, coworker testimony, and facility maintenance logs may help establish the presence of CM-18 Gun Mix at a given job site and during relevant time periods.
  • Preserve medical records. A documented diagnosis from a qualified physician — including pathology reports and imaging — is foundational to any asbestos-related legal claim.
  • Identify all exposure sources. Workers in industrial settings frequently encountered multiple asbestos-containing products. A thorough exposure history may implicate other manufacturers whose products are covered by active trust funds, potentially providing additional avenues for compensation.

Statutes of limitations for asbestos claims vary by state and typically begin running from the date of diagnosis rather than the date of exposure. Prompt consultation with legal counsel is important to preserve all available remedies.

This article is provided for informational and reference purposes. It does not constitute legal advice. Individuals with potential asbestos-related claims should consult a licensed attorney.