The fire resistance rating of steel fire doors is divided into three types. The fire resistance time of Class A steel fire doors shall not be less than 1.5 hours; the fire resistance time of Class B steel fire doors shall not be less than 1.0 hours; the fire resistance time of Class C steel fire doors shall not be less than 0.5 hours.

https://ztfiredoor.com/24752.html

fire rated door half lite entry,louver panel for fire doors,fire door keep clear,ul fire rated door louvers,fire rated door half lite entry,fire door plate,fire door keep shut sign,fire door white,fire door keep clear,fire door keep shut sign,fire door alarm,fire rated door half lite entry,fire door label,fire door keep clear,fire door tag,fire door keep shut sign