This calculation below is the max height for allowance.
Standard vision panel door.
To create the maximum vision panel size incompletion the formula is as follows.
The vision panel bead design is generally a bolection type bead in fire applications although flush beads can be provided as shown.
If the vision panel is fire protective glass such as safety wired glass and safety ceramic its size is limited to no more than 100 square inches whether or not sprinklers are present.
Ada section 404 2 11 requires that at least one of the vision panels in a door and sidelites adjacent to a door be no more than 43 inches 1090 mm above the floor line to provide visibility and safe access for all.
Vision panels exceeding 100 square inches in 60 and 90 minute doors require fire resistive glazing.
The 2012 ibc model building code contains size limits for vision panels in a 60 or 90 minute door.