A spare or extra door fixed ready for use in a roadway in the event of damage to the existing ventilation door. The safety door is also positioned so that it can be employed in any emergency, for example, explosions or fires. The door may be of steel construction.
Security doors are specially designed to provide a higher level of protection than regular doors. Often for commercial use, specialized doors prevent perpetrators from entering or exiting your building. It also serves as your first line of defense against forces like fire, smoke, and storms, among many others.
