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08-001603drn bus driver compartment

Mr. Paul Witkowski

VCA North America

41000 West Seven Mile Road

Suite 140

Northville, MI 48167-2664

Dear Mr. Witkowski:

This responds to your letter asking about Federal Motor Vehicle Safety Standard (FMVSS) No. 217, Bus emergency exits and window retention and release. You ask for guidance on 50 articulated hybrid-driveline buses that a United Kingdom bus manufacturer is manufacturing for sale in Nevada. These buses will be used as transit buses and will include a separate, lockable compartment for the bus driver that is partitioned off from the rest of the vehicle. You wish to know whether FMVSS No. 217 permits the design, i.e., whether under the standard the driver would have adequate access to the buss emergency exits. As explained below, FMVSS No. 217 does not prohibit the separate, lockable compartment specifically described in your letter. However, there are other requirements and safety considerations of which you should be aware.


The National Highway Traffic Safety Administration (NHTSA) is authorized to issue FMVSSs that set performance requirements for new motor vehicles and items of motor vehicle equipment (see 49 U.S.C. Chapter 301). NHTSA does not provide approvals of motor vehicles or motor vehicle equipment. Instead, manufacturers are required to self-certify that their products conform to all applicable safety standards that are in effect on the date of manufacture. The following is an interpretation of our requirements based on the information you provided.

You describe the drivers compartment as having:

a full height tinted glass partition that separates the driver from the main passenger compartment. Access to the drivers compartment is gained from the main passenger compartment through a centrally mounted full depth tinted glass door, that when opened, allows the driver to ascend the two steps to his elevated workplace.

You explain that the cab door is spring loaded and will close behind the driver entering the compartment. The driver has two ways of locking the door. The first way is by manually operating a handle on the door to lock the door. To release the lock and open the door, the driver rotates the handle 90 degrees clockwise. The second way is by pushing a button from the drivers seat that electrically operates a shoot bolt which mechanically extends a steel bar into a mating hole in the door. To release the lock, the button is pressed again. You state that the electronic locking feature requires constant electrical power to remain locked, and will open upon loss of electrical power.

You also state that the drivers compartment has one side window to the left of the driver that has a sliding portion that can open for ventilation and to allow the driver to adjust the exterior mirror. The glass on the right side of the drivers compartment does not open.[1] We assume that neither of these two side windows meets the requirements for emergency window exits of FMVSS No. 217.


FMVSS No. 217 applies to buses, except buses manufactured for the purpose of transporting persons under physical restraint. (See S3.) Among other purposes, FMVSS No. 217 is intended to provide a means of readily accessible emergency egress. (See S2.) FMVSS No. 217 states in part at S5.2.2.1: Buses other than school buses shall provide unobstructed openings for emergency exit which collectively amount, in total square centimeters, to at least 432 times the number of designated seating positions on the bus.

The main question presented by your letter is whether the bus provides the driver unobstructed openings for emergency exit. In your design, the driver is separated from the passenger compartment that has the emergency exits but still is able to readily access those exits. The driver can manually unlock and open the door in one or two motions, and the lock will also automatically disengage the locking mechanism in the event of an electrical failure. Because of these features, in our opinion FMVSS No. 217 does not prohibit your design. Keep in mind that the bus drivers seating position must be counted in the S5.2.2.1 calculation of required unobstructed openings for emergency exit.

There are other requirements and safety considerations of which you should be aware. Because you describe the compartment as made of tinted glass, the bus manufacturer must ensure that the compartment meets all applicable requirements of FMVSS No. 205, Glazing materials. FMVSS No. 205 applies to buses and to glazing materials used in those vehicles. (See S3.1(a).)

States have the authority to regulate the use of vehicles and may have laws pertaining to the drivers access to an emergency exit or to other aspects relating to your vehicle. You should check State law to see how they affect your vehicles.

If you have any further questions, please contact Dorothy Nakama of my staff at (202) 366-2992.

Sincerely yours,

Anthony M. Cooke

Chief Counsel



[1] You enclosed photographs of a bus that was manufactured for use in the U.K. To clarify the photographs, based on a telephone conversation between you and Dorothy Nakama of my staff, we note that the window you say is to Drivers LH Side (page 4 of your letter) is actually, in the photograph, to the drivers right hand side of that bus. The same is noted for the window to drivers right hand side. It is actually to the drivers left side in the photograph.