.31 Emergency Door.

A. Emergency exits shall be in accordance with the requirements of 49 CFR §571.217, with the following additions:

(1) The rearmost seats shall be spaced to provide an unobstructed exit; and

(2) The words "Emergency Door" shall be 2 inches high by 3/8 inch wide black lettering and shall be applied above the door and emergency push-out windows on the inside and outside of the vehicle. If the outside areas above the door or the upper door window are not large enough for the words, the words may be placed on the door under the upper window.

B. There shall be a head bumper pad sufficient to reduce the likelihood of injury upon impact installed on the inside of the vehicle at the top of the emergency door. The pad shall:

(1) Be 4 inches wide; and

(2) Extend across the entire top of the door opening.

C. Passage to the emergency door shall be kept clear of obstructions.

D. Slide Bar Latch.

(1) The emergency door or doors shall be equipped with a slide bar-type latch which shall extend into or overlap the door frame by not less than 1 inch.

(2) If a vertical slide bar latch system is used, it shall simultaneously engage latch plates in both the floor and overhead structure not more than 4-1/2 inches from the opening side of the door or doors.

(3) The outside handle of the slide bar latch shall be installed so as to minimize hitching and shall be a nondetachable device.

E. An automatically operated, distinctive audible signal shall clearly indicate to the seated driver, when the engine is running, the unlatching of the emergency door or doors. A cut-off switch except through the ignition switch may not be installed in the circuit.

F. The upper and lower portion of a central rear emergency door shall be equipped with approved safety glass, the exposed area of which shall be not less than 400 square inches in the upper portion and not less than 300 square inches in the lower portion.

G. Prohibitions.

(1) There may not be steps leading to the emergency door; and

(2) The engine starting system of a bus may not operate if any emergency exit is locked from either inside or outside the bus.