ASTM C578-14

1.1 This specification² covers the types, physical properties, and dimensions of cellular polystyrene boards with or without facings or coatings made by molding (EPS) or extrusion (XPS) of expandable polystyrene. Products manufactured to this specification are intended for use as thermal insulation for temperatures from -65 to +165°F (-53.9 to +73.9°C). This specification does not apply to laminated products manufactured with any type of rigid board facer including fiberboard, perlite board, gypsum board, or oriented strand board.

1.1.1 For Type XIII only, this specification covers the physical properties, and dimensions of cellular polystyrene intended for use as thermal insulation for temperatures from −297 to +165°F (−183 to +73.9°C).