Modern fire rated exterior doors with glass
External Fire Doors – Features, Purpose And Installation Tips For The Beginner : Modern Fire Rated Exterior Doors With Glass
Quote from Article entitled External Fire Doors – Features, Purpose And Installation Tips For The Beginner:
This applies to large buildings such as office blocks and apartment buildings where there is a risk of multiple casualties in case of fire. It appears as a requirement under different building codes. This doesn’t apply to all states but the logic and purpose is undeniable.
The full version of the article can be found here.