NFPA 101 now states a max height::
NFPA 101-2018, 7.10.1.9:
7.10.1.9 Mounting Location. The bottom of new egress markings
shall be located at a vertical distance of not more than 6 ft
8 in. (2030 mm) above the top edge of the egress opening
intended for designation by that marking. Egress markings
shall be located at a horizontal distance of not more than the
required width of the egress opening, as measured from the
edge of the egress opening intended for designation by that
marking to the nearest edge of the marking.
Now if someone would ban "fire exit"
NFPA 101-2018, 7.10.1.9:
7.10.1.9 Mounting Location. The bottom of new egress markings
shall be located at a vertical distance of not more than 6 ft
8 in. (2030 mm) above the top edge of the egress opening
intended for designation by that marking. Egress markings
shall be located at a horizontal distance of not more than the
required width of the egress opening, as measured from the
edge of the egress opening intended for designation by that
marking to the nearest edge of the marking.
Now if someone would ban "fire exit"