Ms. Carrie Stabile
85 Sedge Road
Valley Cottage, NY 10989

Dear Ms. Stabile:

This responds to the letter from you and your brother James Stabile regarding a "Vehicle Illuminated Warning System" that you wish to market for school buses. You have asked for its "review with regards to Vehicle Safety Standards."

While your cover letter did not describe your Warning System in detail, it appears from your enclosed sketches that the system consists of panels centered in the front and rear headers through which the bus operator may provide certain illuminated messages to other drivers. These are "School Bus" (in green), "Slow Down" (yellow), and "Do Not Pass" (red).

You indicated to Dee Fujita of my staff that you might design the system such that the messages are automatically activated in certain circumstances. You are considering designing the system such that the "School Bus" message would be illuminated while the vehicle is moving, "Slow Down" would show when the school bus driver brakes, and "Do Not Pass" when the vehicle's red lamps are activated. The message board is rimmed by small yellow and red lamps. The small yellow lamps would flash with the Slow Down message and the small red lamps would flash with "Do Not Pass."

The short answer is there is no Federal motor vehicle safety standard (FMVSS) that specifies requirements for your Warning System. However, as explained below, your system is regarded as supplementary lighting equipment, which subjects it to certain requirements. Further, the States have the authority to regulate the use of school buses, including how the vehicles are identified. Thus, States might have requirements affecting whether your message board is permitted on school buses operating in each jurisdiction.

By way of background, the National Highway Traffic Safety Administration (NHTSA) is authorized by Congress (49 U.S.C. Chapter 301) to issue FMVSSs that set performance requirements for new motor vehicles and new items of equipment. NHTSA has used this authority to issue Standard No. 108, Lamps, Reflective Devices and Associated Equipment. NHTSA does not approve motor vehicles or motor vehicle equipment, nor do we endorse any commercial products. Instead, our statute establishes a "self-certification" process under which each manufacturer is responsible for certifying that its products meet all applicable safety standards. The following represents our opinion based on our understanding of the information you provided.

To answer your letter, we will first discuss the Federal lighting requirements that apply to your system generally. Following that, we will discuss specific issues about your system.

General lighting requirements In addition to the lighting equipment required for ordinary buses, paragraph S4.1.4 of Standard No. 108 requires school buses to be equipped with a system of four red signal lamps, or four red and four amber signal lamps, designed to conform to SAE Standard J887 School Bus Red Signal Lamps, July 1964, and installed at the top and evenly spaced from the vertical centerline of the bus. These lamps must flash alternately at a rate of 60-120 cycles per minute. All other required lighting equipment, except for turn signals and hazard warning signals, must be steady- burning.

Supplementary lighting equipment is permissible under the following conditions. If your Warning System is to be installed by a manufacturer or dealer before the first sale and delivery of the school bus, the Warning System must not impair the effectiveness of the lighting equipment required by Standard No. 108 including the signal system mentioned above, that is to say, it cannot replace required equipment, or modify its performance or detract from the "message" that the required lamp is intended to impart. Manufacturers of motor vehicles are required to affix a certification to the vehicle that it complies with all applicable Federal motor vehicle safety standards, and the determination of impairment is to be made by the manufacturer at that time. A dealer installing the Warning System is regarded as an alterer, and required to affix its own certification that the vehicle as altered continues to conform; at that point, the dealer installing the system would make its determination that impairment did not exist. NHTSA will not contest a determination unless it is clearly erroneous.

If the Warning System is to be installed on school buses already delivered and in use, there is no Federal requirement that the person adding the equipment certify the vehicle. However, there is a similar obligation to ensure continuing compliance. If the person is a manufacturer, dealer, distributor, or motor vehicle repair business, under a statute that we administer, that person must ensure that installation and use of the Warning System will not "make inoperative" any of the required lighting equipment including the school bus signal lamp system. We regard "making inoperative" in this context the equivalent of "impairment" discussed in the previous paragraph.

The statute permits an exception to the above: modifications of any nature made by the school bus owner itself in its own repair facilities are not prohibited by our statute.

Specific issues concerning "impairment" As noted above, the Warning System may be installed on new school buses if it does not impair the effectiveness of the lighting equipment required by Standard No. 108. "Impairment" can occur in different ways. One way could be by interfering with the performance of required lamp systems, including the required school bus warning lamps or the brake warning lamps. The following are examples of interference:

C Your system could not replace the identification lamps required by Standard No. 108.

C It must not cause the yellow-red warning system to flash sequentially, rather than alternately as required by the standard.

C The Warning System must not cause the flashing of lights that must be steady- burning (e.g., the stop and taillamps, which, under Standard No. 108, must be steady- burning at all times). Your system appears to have a deceleration warning system operating through either original equipment lamps or supplementary ones. The lamps for the system must be steady-burning, and cannot flash. For the same reason, the little lights around the message board must not flash with the "Slow Down" and "Do Not Pass" messages.

"Impairment" can also occur when an operator is distracted from the driving task, even momentarily. For this reason, we have discouraged the concept of message boards over the years. However, this is the first time we have been asked to consider it in the context of school bus lighting. We find that there are considerations that are relevant to the operation of school buses, that do not apply to other vehicles. A driver behind a school bus, or approaching from an opposite direction, is more likely to be cautious because of the awareness of the importance of child safety and the penalties involved in infractions of traffic laws relating to school buses. There is less possibility of impairment existing with advisories relating directly to the actions other drivers are presumably anticipating when in the vicinity of a school bus. With this in mind, we believe your message board, which sends only three messages--an identification of the vehicle as "School Bus" and advisories of "Slow Down" and "Do Not Pass"--generally would be permitted under Standard No. 108.

There are a number of specific features about your message board, however, that could distract a driver, and thus constitute "impairment." These are as follows:

C Your sketch indicates that the lamps used for the "School Bus" message would be green. Standard No. 108 restricts the color of required exterior lights to red, amber, and white, the former two of which are associated with caution. Green is not used as an exterior lighting color because it is the recognized signal to proceed rather than to warn. We believe that use of the color green has the potential to create a measure of confusion rather than caution, thereby affecting the effectiveness of the mandatory lighting equipment.

C Another feature that could distract a driver is the message "Slow Down," which automatically illuminates anytime the school bus driver brakes. We believe this could be confusing to drivers in other lanes and oncoming vehicles, since it may lead some drivers to believe the school bus is preparing to stop, when the bus is not. A less confusing feature would be if the Slow Down message is illuminated only when the amber school bus warning lamps flash, and not each time the driver brakes.

State requirements Because your Warning System is not a Federally required item of lighting equipment, its use is also subject to regulation under the laws of the States in which it may be used. Each State regulates the use of school buses in its highway safety programs, setting requirements for pupil transportation safety, including the identification of school buses. NHTSA has issued a number of Highway Safety Program Guidelines for States to use in establishing their highway safety programs. Guideline No. 17, "Pupil Transportation Safety" (copy enclosed) has recommendation that might affect your message board, if the State has decided to adopt the recommendation as State law. The Guideline recommends that school buses should, among other things,

Be identified with the words "School Bus" printed in letters not less than eight inches high, located between the warning signal lamps as high as possible without impairing visibility of the lettering from both front and rear, and have no other lettering on the front or rear of the vehicle, except as required by Federal Motor Vehicle Safety Standards (FMVSS), 49 CFR part 571. (Section IV.B.1.a.)

Depending on the requirements a State has adopted for identifying school buses, the State might limit how your message board displays the words "School Bus," and the "Slow Down" and "Do Not Pass" messages. If you have questions about State law requirements, we suggest you consult the American Association of Motor Vehicle Administrators for an opinion. Its address is 4600 Wilson Boulevard, Arlington, Va. 22203.

We appreciate the interest that you and your brother have shown in improving the safety of school children. If you have any further questions, you may call Dee Fujita (202-366-2992) or Taylor Vinson of this office (202-366-5263).


Samuel J. Dubbin Chief Counsel


ref:108 12/11/95

NHTSA also has the authority to investigate safety-related defects. Manufacturers of motor vehicles and items of motor vehicle equipment (such as your Warning System) must ensure that their products are free of safety-related defects.