SG20 Glass Fire Door
Locks for fire rated doors
As a general rule to achieve the fire rating, single action (rebated) doors must have a mortice lock and latch with additional top locking point and a drop seal. Therefore they require lever handles or activated pull handles that retract the latch.
Double action doors have an intumescent layer that cannot be milled out for locks/latches. These generally have surface mounted pull handles.
One exception to this is a single action door available with plain meeting stiles. This must have an anti finger trap stile which means no latch can be used.