what is millboard used for
Millboard is a thick, square piece of asbestos based insulation that was used in walls, furnaces, fire screens and in other areas where large amounts of heat were produced.ad it not been for the discovery of its poisonous nature, asbestos would most likely still be commonly used by manufacturers throughout the United States. The mineral was mined and processed by hundreds of American companies for nearly a century before its toxicity was revealed.