Fire doors cannot prevent fire. The main purpose of fire doors is to localize the place of fire, that is, to prevent the fire from spreading to other rooms.
They are classified according to how long they are able to withstand temperatures less than 180 degrees on the non-fire side. This time is measured in minutes from the beginning of the impact of fire on the door to the onset of any of the limiting states (structural failure, loss of integrity and thermal insulation qualities).
The fire resistance limit of the door is indicated by a Latin letter corresponding to one of the limit states, and numbers showing the time in minutes before the onset of this limit state.
Thus, in order to understand what the expression fire doors ei 60 means, you need to familiarize yourself with the list of limit states of doors for fire resistance and the corresponding Latin letters:
R is the loss of the bearing capacity of the structure due to collapse or the occurrence of ultimate deformations;
E — loss of integrity due to the formation of through cracks in the door through which the flame and combustion products begin to penetrate the surface that is not facing the fire;
I — loss of heat-insulating ability due to heating of the side not facing the fire to the limit values.
So, if a door has a fire resistance of EI 60, this means that it is able to withstand the effects of a flame for 60 minutes, without heating to extreme values and without losing its integrity. That is, within an hour the fire will not be able to break through such a door..
Such doors are installed in office and warehouse premises, factory premises. There are fire doors that can withstand a longer time of contact with a fire, but they are usually installed in special cases in special buildings. The structure of the EI 60 doors consists of two sheets of galvanized steel with a minimum thickness of 0.8 mm, between which there is a layer of mineral wool. In other cases, a complex thermal package is used to protect against fire. The door leaf thickness reaches 63 mm. Fire doors are produced without a threshold.
Fire doors are a reliable way to protect residential and office premises from fire and minimize negative consequences in the event of a fire.