Interpretation ID: aiam5380
Engineering Truck Trailer Manufacturers Association
1020 Princess Street
Alexandria, Va. 223l4
Dear Mr. Vierimaa: We are replying to your letter of August 9, 1993 with respect to your views on the enforceability of a section of the Michigan Motor Vehicle Code. This issue apparently arose in correspondence between you and the Michigan Department of State Police in May 1989. Under Section 719(8)(c) of the Michigan Code, a 'semitrailer' whose overall length is more than 50 feet is required to be equipped with 'two clearance lamps, 1 on each side of the semitrailer, located at 1/2 the distance from the front to the rear and as near to the top of the semitrailer as practicable.' In your letter of May 12, 1989, to the State Police, you stated your assumption that the 'two clearance lamps' are the 'intermediate side marker lamps' specified in Federal Motor Vehicle Safety Standard No. 108, and, if Michigan is requiring two additional intermediate side marker lamps, 'then it would appear that your requirement is invalid as FMVSS 108 preempts State regulations which substantially differ.' In support of your views, you provided Michigan with copies of relevant NHTSA interpretations. Michigan replied on May 16, 1989, that NHTSA had not notified it that 'the requirement of an additional 'clearance lamp' as near as to the top of the semitrailer as practicable is preempted by section 103(d)', and that 'the lamp is not a marker lamp as mentioned in 1.7 of the DOT interpretations.' You indicate that this is a reference to our letter of December 10, 1974, to the California Highway Patrol. You ask for our concurrence in your conclusion that Michigan is preempted from enforcing its requirements. The Federal motor vehicle safety standard on motor vehicle lighting is 49 CFR 571.108 Motor Vehicle Safety Standard No. 108 Lamps, Reflective devices, and Associated Equipment. Table II of Standard No. 108 applies, in pertinent part, to trailers of 80 or more inches overall width, and requires them to be equipped with front and rear side marker lamps as far to the front and to the rear as practicable, and with 'intermediate side marker lamps', amber in color, 'located at or near the midpoint between the front and rear side marker lamps.' All side marker lamps are to be mounted not less than 15 inches above the road surface. However, paragraph S5.1.1.3 states that intermediate side marker devices are not required on vehicles less than 30 feet in overall length. Section 103(d) of the National Traffic and Motor Vehicle Safety Act (l5 U.S.C. 1392(d)) states that whenever a Federal motor vehicle safety standard is in effect, no State 'shall have any authority either to establish or continue in effect with respect to any motor vehicle . . . any safety standard applicable to the same aspect of performance of such vehicle . . . which is not identical to the Federal standard' (emphasis added). In our opinion, the 'aspect of performance' covered by Section 719(8)(c) of the Michigan Code is the side conspicuity of extra long trailers, the same 'aspect of performance' that is addressed by the requirements of Table II that I have discussed in the preceding paragraph. Because Standard No. 108 requires trailers more than 50 feet in length to be equipped with intermediate side lamps located not less than l5 inches above the pavement, any State requirement that such trailers be equipped with a supplementary set of lamps in the same approximate vertical plane but as near the top of the trailer as practicable is preempted by Table II of Standard No. 108. The fact that Michigan calls the lamp a 'clearance' lamp rather than a 'marker' lamp does not affect this conclusion (in fact, we regard all non-signal lamps other than headlamps as 'marker' lamps, including the 'clearance' lamps Table II requires on the front and rear of wide trailers). The purpose of the preemption clause is to relieve the burden on interstate commerce that would result from a manufacturer having to meet more than one set of safety requirements to address the same safety concern. It does not affect the right of a State to establish its own safety requirements in areas where there are no Federal ones. The interpretation provided the California Highway Patrol is consistent with this one. There we advised that to the extent that California law prohibited multiple marker lamps or prescribed different mounting requirements other than as permitted by Standard No. 108, those laws were preempted by section 103(d).
Sincerely, John Womack
Acting Chief Counsel