This part of IEC 61249 gives requirements for properties of non-halogenated epoxide non-woven/woven reinforced E-glass laminated sheets of defined flammability (vertical burning test), copper-clad in thicknesses of 0,80 mm up to 1,60 mm. The flammability rating is achieved through the use of non-halogenated inorganic and/or organic compounds acting as fire retardants. These fire retardants are contained as part of polymeric structure or in addition to it. The glass transition temperature is defined to be 95 °C minimum.