Moulded expanded polystyrene (EPS) is an air-filled, closed-cell, rigid foam plastic that does not contain any hydrochlorofluorocarbons (HCFCs) or hydrofluorocarbons (HFCs) as blowing agents. The closed-cell structure of EPS insulation provides constant thermal resistance, is dimensionally stable and non-corrosive, provides excellent mechanical properties, and can be recycled where facilities exist.