Exterior fire rated door
External Fire Doors – Features, Purpose And Installation Tips For The Beginner : Exterior Fire Rated Door
Quote from Article entitled External Fire Doors – Features, Purpose And Installation Tips For The Beginner:
Typically, fire doors are meant to remain closed at all times in order to serve their purpose of preventing fire spreads. Different mechanisms including positive latch systems and electromagnetic locks are employed in this case. However, there are some that are modified to also serve as emergency exit routes. In this case, they are easy to open but will lock themselves immediately the people pass.
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