1.1 ,This specification covers expanded or exfoliated vermiculite thermal insulating material in the form of dry cement or plaster, intended to be mixed with a suitable proportion of water, applied as a plastic mass, and dried in place, for use as insulation on surfaces operating at temperatures between 100°,F (38°,C) and 1800°,F (982°,C). The cement shall not be used where it will be exposed to combustion conditions, such as the hot face lining of a furnace.