E (Integrity): hot gas and flame-proof the endurance of the door
The mortality in fires incurs fire by fainting because of being affected by smoke.
I (Insulation): the endurance of responding to the temperature of
the surface which incurs flame. In other words, transferring the
heat to the flame’s other side.
A door with EI120 certificate has all fire resistance. B-DOORS fire
doors have the certificate of EI-120