Captain Ormond L. Cox, "Heat Insulation" (1936)

An 18-page offprint of a paper by Captain Ormond L. Cox of the U.S. Navy, director of the U.S. Naval Engineering Experiment Station at Annapolis, read before the Society of Naval Architects and Marine Engineers in November 1936. Cox describes how the Navy tested heat insulation for ships (heat loss, durability, ease of application and weight) and the materials it had approved: molded high-temperature insulation, felted rock wool, aluminum foil, insulating cements, asbestos pads and blankets, and asbestos tape. The old standby, 85% Magnesia, could not be used on the hotter steam lines of newer ships, and he wrote that "no single material will meet all of the requirements."

What it shows

The paper is about heat, weight, durability and cost; it does not discuss health. It shows that by 1936 the Navy had already approved insulation with little or no asbestos for some uses, such as rock wool and aluminum foil, alongside asbestos products. The printed discussion includes engineers from the insulation industry. R. W. Mollison of Keasbey & Mattison described a new method of spraying asbestos fiber onto ships' surfaces, using "crocidolite asbestos fiber, known in the trade as Cape blue fiber" (Crocidolite), already used on the French liner Normandie and on American oil tankers. R. C. Parlett of the Johns-Manville Corporation agreed with Cox that no single insulating material would meet every need.