Staz-on Insulating Cement (NARCO)

Product Description

Staz-on Insulating Cement was a refractory insulating cement manufactured by North American Refractories Company (NARCO), a major producer of refractory materials headquartered in the United States. The product was produced primarily during the 1960s and 1970s and was designed for use in high-temperature industrial environments where reliable thermal insulation and structural integrity were essential. Staz-on was marketed and sold as a specialty cement capable of withstanding extreme heat conditions, making it a preferred material in steel mills, refineries, power plants, chemical processing facilities, and other heavy industrial settings.

Refractory cements like Staz-on served a critical function in industrial operations: they were applied to furnaces, kilns, boilers, ovens, and other high-heat equipment to insulate and protect the underlying structure. Staz-on was used both as a setting and patching cement for refractory brick and as a stand-alone insulating layer in applications where controlled thermal performance was required. Its hydraulic cement binder formulation allowed it to bond effectively with refractory shapes and other masonry materials, and workers valued the product for its workability and high-temperature durability.

NARCO was one of the leading refractory manufacturers in the country during this era and supplied materials to a wide range of industries. Staz-on Insulating Cement was distributed broadly through industrial supply channels and appeared on job sites across multiple trade sectors. Its widespread use during the peak decades of asbestos-containing refractory product manufacturing means that significant numbers of workers in several trades encountered the product during their careers.

Asbestos Content

Staz-on Insulating Cement contained chrysotile asbestos incorporated into its hydraulic cement binder. Chrysotile, also known as white asbestos, was the most commercially widespread form of asbestos used in industrial products during the mid-twentieth century. In refractory cements, chrysotile fibers were added to improve tensile strength, resist thermal cracking, and enhance the material’s ability to maintain structural cohesion under repeated heating and cooling cycles. The hydraulic cement binder system allowed the product to cure and harden in place, locking fibers into the set material — but only until the cement was disturbed through mixing, application, removal, or repair.

The inclusion of chrysotile asbestos in hydraulic cement binders was a documented industry practice during the 1960s and 1970s. Refractory product manufacturers, including NARCO, utilized asbestos in this class of products before regulatory actions by the Occupational Safety and Health Administration (OSHA) and the Environmental Protection Agency (EPA) prompted reformulation or discontinuation of asbestos-containing lines. AHERA (the Asbestos Hazard Emergency Response Act) and subsequent federal regulations established standards for identifying and managing asbestos-containing materials, recognizing the health hazards associated with all commercially used asbestos fiber types, including chrysotile.

How Workers Were Exposed

Exposure to asbestos fibers from Staz-on Insulating Cement occurred across multiple stages of the product’s use, from initial mixing through application, curing, and eventual repair or removal. The following trades were documented as having regular or incidental contact with the product:

Refractory Workers faced the most direct and sustained exposure to Staz-on. These workers were responsible for constructing and maintaining the refractory linings of industrial furnaces, kilns, and other high-heat equipment. Mixing the dry cement powder with water to achieve a workable consistency generated airborne dust heavily laden with asbestos fibers. Troweling, applying, and finishing the cement on vertical and overhead surfaces further disturbed the material and kept fiber concentrations elevated in enclosed or poorly ventilated work areas.

Industrial Maintenance Mechanics encountered Staz-on during routine maintenance and repair of plant equipment. Boilers, heat exchangers, and process vessels lined or patched with the cement required periodic inspection and upkeep. Breaking out deteriorated refractory cement to access equipment internals — and then reapplying new cement — created significant dust events. Mechanics often worked in confined spaces where airborne fiber concentrations could accumulate rapidly.

Ironworkers worked in proximity to refractory cement applications in steel mill and foundry environments, where furnaces and related structures were a constant presence on the job site. Even when ironworkers were not applying the cement themselves, work performed in the same areas where Staz-on was being mixed or installed exposed them to secondhand fiber release.

Boilermakers built and repaired boilers and pressure vessels in industrial and utility settings where Staz-on was a standard insulating material. Cutting, chipping, and grinding operations on cured refractory cement — as well as the demolition of old boiler insulation to facilitate repair work — released chrysotile fibers into the breathing zone of boilermakers and others working nearby.

In all of these exposure scenarios, the risk was compounded by the workplace conditions typical of industrial sites during the 1960s and 1970s: limited respiratory protection, inadequate ventilation, and an incomplete understanding among workers of the health hazards associated with asbestos inhalation. Diseases linked to occupational asbestos exposure — including mesothelioma, asbestosis, and lung cancer — can have latency periods of 20 to 50 years, meaning that workers exposed to Staz-on during this period may only now be receiving diagnoses.

Documented Product Identification

The following details are drawn from public asbestos litigation records, manufacturer catalog pages, technical manuals, and corporate history materials. Each item reflects the product as documented in those sources.

Corporate context: Formed in 1929 through the merger of several refractory companies including Queen’s Run, Crescent, and Eltra, among others. Owned by Eltra until 1979, then by Allied Signal (Allied) from 1979 to 1986, after which ownership transferred to banks and investors. Headquartered in Cleveland, Ohio.

Brand identification: Narco

Industries served: steel, iron.

North American Refractories Company (Narco) manufactured refractory materials used primarily in high-temperature industrial applications such as steel and iron processing. The company operated approximately eleven manufacturing facilities and a research center in Curwensville, Pennsylvania.