Pabco Caltemp Block and Pipe Covering

Product Description

Pabco Caltemp Block and Pipe Covering was a high-temperature thermal insulation product manufactured by Fibreboard-Pabco from approximately 1950 through 1968. Marketed under the Pabco brand — a product line of the Fibreboard Corporation — Caltemp was engineered for industrial and commercial applications requiring durable, heat-resistant insulation on pipes, boilers, tanks, and other high-temperature equipment.

The product was sold in two primary forms: rigid block sections designed to insulate flat and curved surfaces such as boiler walls and ductwork, and preformed pipe covering sections shaped to fit around pipes of varying diameters. Both forms were designed to withstand the elevated temperatures typical of industrial processing facilities, power generation plants, petrochemical refineries, and U.S. Navy vessels and shipyards.

Caltemp was widely specified throughout American industry during the postwar manufacturing boom. Its combination of thermal efficiency, compressive strength, and relatively low cost made it a standard choice for insulation contractors and industrial facilities from the early 1950s through the late 1960s. The product was distributed nationally and appears in trade catalogs, industrial supply records, and shipyard procurement documents from the period of its production. Fibreboard-Pabco ceased producing asbestos-containing versions of Caltemp by 1968, corresponding broadly with the period during which scientific and regulatory attention to asbestos hazards began to intensify.

Asbestos Content

Pabco Caltemp Block and Pipe Covering was formulated using chrysotile asbestos fibers bound within a calcium silicate matrix. The calcium silicate base material provided the structural rigidity and thermal resistance necessary for high-temperature applications, while the chrysotile asbestos content contributed reinforcement, additional heat tolerance, and dimensional stability under repeated thermal cycling.

Chrysotile is the most commonly used form of asbestos in manufactured insulation products of this era. Like other asbestiform minerals, chrysotile consists of microscopic fibers that can be released into the air when the material is cut, abraded, or otherwise disturbed. The calcium silicate matrix of Caltemp was rigid and friable under mechanical stress — meaning that routine installation and removal activities could readily generate airborne fiber concentrations.

The specific percentage of chrysotile asbestos in Pabco Caltemp formulations varied across production years, which was typical for calcium silicate insulation products of the period. Regulatory frameworks such as AHERA and OSHA’s asbestos standards, established in later decades, confirmed that calcium silicate insulation products from this era commonly contained asbestos at levels sufficient to present significant occupational health hazards, particularly under conditions of repeated disturbance.

How Workers Were Exposed

Workers in several skilled trades encountered Pabco Caltemp Block and Pipe Covering regularly during the product’s years of production and, critically, during subsequent maintenance, repair, and removal work that continued long after 1968.

Insulators (AWIU) — Members of the Asbestos Workers International Union were the primary installers of Caltemp block and pipe covering. Installation required cutting preformed pipe sections and block material to fit specific dimensions using hand saws, knives, and abrasive tools. These cutting operations generated substantial quantities of airborne chrysotile dust in enclosed mechanical rooms, shipboard compartments, and industrial facilities where ventilation was often limited or nonexistent.

Pipefitters — Pipefitters working alongside insulation crews were exposed to Caltemp dust during the installation and fitting of insulated pipe systems. They also encountered previously installed Caltemp when performing maintenance or modifications to piping systems, requiring the removal of existing insulation — a process that disturbed friable, aged material and released fiber concentrations potentially far greater than during original installation.

Boilermakers — Boilermakers were regularly exposed to Caltemp block insulation during the construction, maintenance, and repair of boilers in industrial and utility settings. Removing and replacing insulation blocks from boiler surfaces, and working in close proximity to insulation work performed by other trades, placed boilermakers in frequent contact with airborne chrysotile fibers.

Navy Shipyard Workers — U.S. Navy vessels and shore-based shipyard facilities were significant users of Caltemp pipe covering during the 1950s and 1960s. Shipboard machinery spaces, engine rooms, and boiler rooms were heavily insulated environments in which multiple trades worked in close quarters. Navy shipyard workers — including insulators, pipefitters, machinists, and laborers — were exposed both during new ship construction and during overhaul and repair work in which old insulation was disturbed or removed.

Exposure did not end with the product’s manufacture. Caltemp installed before 1968 remained in place in countless facilities and vessels for decades afterward. Workers performing maintenance, renovation, or demolition in subsequent years — often without adequate respiratory protection, because hazard communications requirements did not yet exist — continued to encounter friable Caltemp material containing chrysotile asbestos.

Diseases documented in workers with occupational histories involving asbestos-containing insulation products such as Caltemp include mesothelioma, asbestosis, lung cancer, and other asbestos-related conditions. These diseases typically have latency periods of 20 to 50 years between exposure and diagnosis.

Fibreboard Corporation Asbestos PI Trust

Pabco Caltemp Block and Pipe Covering is a documented product of the Fibreboard Corporation, and claims involving this product are eligible for submission to the Fibreboard Corporation Asbestos PI Trust. The trust was established as part of Fibreboard Corporation’s bankruptcy reorganization proceedings, which resolved the company’s substantial asbestos-related liabilities through a structured settlement fund. Trust funds of this type are a common legal mechanism in asbestos litigation, allowing injured workers and their families to obtain compensation without filing individual lawsuits.

Claimants submitting to the Fibreboard Corporation Asbestos PI Trust should be prepared to document:

  • Product identification — Evidence that Pabco Caltemp (manufactured by Fibreboard-Pabco) was present at the specific job sites or vessels where the claimant worked
  • Occupational history — Employment records, union records, coworker affidavits, or other documentation confirming work in trades and locations where Caltemp was used during the period 1950–1968 (or during subsequent maintenance/removal of previously installed Caltemp)
  • Medical diagnosis — Physician-documented diagnosis of an asbestos-related disease such as mesothelioma, lung cancer, asbestosis, or pleural disease
  • Exposure period — Documentation establishing the timeframe and nature of asbestos exposure consistent with trust eligibility requirements

Typical claim categories eligible under asbestos PI trusts include mesothelioma claims, lung cancer claims, and nonmalignant asbestos disease claims, with compensation levels and documentation requirements varying by disease category. Trust claim forms, submission deadlines, and specific eligibility criteria are governed by the trust’s current Trust Distribution Procedures (TDP).

Individuals diagnosed with an asbestos-related illness and who worked with or around Pabco Caltemp Block and Pipe Covering — including insulators, pipefitters, boilermakers, and Navy shipyard workers — should consult with an attorney experienced in asbestos trust fund claims. Legal counsel can assist in identifying all applicable trusts and litigation options, as many exposed workers have potential claims against multiple asbestos product manufacturers.