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Interpretation ID: 9508

Mr. Carl Haywood
Operations Manager
Emergency Response Specialists
2251 Happy Top Road
Morris, Alabama 35116

Dear Mr. Haywood:

This responds to your letter of December 21, 1993, requesting information about seating requirements for emergency response units you are designing to respond to chemical spills. The response units are tractor trailer combinations which can be driven in and out of the cargo bay of C-130 Hercules aircraft which are used to transport the units to the site. You further describe the response units as follows:

Our response units are designed to transport all six (6) of our response team members, for over the highway transportation three (3) of our team members will ride in the tractor and the remaining three (3) will ride in the trailer. During air transportation all six (6) team members will ride in the trailer. By providing seating with lap and shoulder restraints in the response unit for both ground and air transportation we eliminate the need for special crew cabins for air transportation, and extra vehicles for ground transportation. This conserves the limited space available on the C-130 allowing us to carry all the equipment needed to respond effectively to large scale chemical releases.

You requested information on the regulation of the seating in the response units. You have already contacted several Department of Transportation agencies, including the Federal Aviation Administration.

I am pleased to have this opportunity to explain our regulations to you. Some background information on Federal motor vehicle safety laws and regulations may be helpful. Our agency is authorized, under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1381 et seq., Safety Act), to issue safety standards applicable to new motor vehicles and items of motor vehicle equipment. The Safety Act defines the term "motor vehicle" as follows:

any vehicle driven or drawn by mechanical power manufactured primarily for use on the public streets, roads, and highways, except any vehicle operated exclusively on a rail or rails.

If a vehicle is a "motor vehicle" under the definition, then the vehicle must comply will all applicable safety standards, including those related to seating and occupant restraint. However, if a vehicle is not a motor vehicle under this definition, then the vehicle need not comply with the agency's safety standards because such a vehicle is outside the agency's scope of authority.

Applying this definition to the response units, NHTSA believes the response units are motor vehicles within the meaning of the Safety Act. In determining whether a vehicle which has both on-road and off-road uses is a motor vehicle, the agency looks at whether the vehicle uses public roads on a necessary and recurring basis. Applying this criteria to the response units, we believe that the response units have a primary function of highway transportation of personnel and equipment to the chemical spill site.

NHTSA's safety standards specify different requirements for different types of motor vehicles. Therefore, in order to determine the occupant seating requirements for the response units, it is necessary to determine how these vehicles are classified under our regulations. NHTSA defines a "truck" as "a motor vehicle with motive power, except a trailer, designed primarily for the transportation of property or special purpose equipment." The tractor portion of the response unit has seating capacity for at least three passengers, but its primary use appears to be to draw the trailer. Therefore, it appears that this vehicle is a "truck" for the purpose of Federal regulations.

NHTSA defines a "trailer" as "a motor vehicle with or without motive power, designed for carrying persons or property and for being drawn by another motor vehicle." NHTSA believes the trailer portion of the response units would be considered trailers for the purpose of Federal regulations.

NHTSA has exercised its authority under the Safety Act to issue four safety standards relevant to occupant seating and restraint: Standard No. 207, Seating Systems, Standard No. 208, Occupant Crash Protection, Standard No. 209, Seat Belt Assemblies, and Standard No. 210, Seat Belt Assembly Anchorages.

Standard No. 207 establishes strength and other performance requirements for all "occupant seats" in passenger cars, multipurpose passenger vehicles, and trucks, and for the driver's seats in buses, except that the requirements do not apply to side-facing seats. Therefore, all "occupant seats" in tractor portion of the response units must meet the requirements of Standard No. 207. Standard No. 207 does not apply to trailers, therefore, the seats in the trailer portion of the response units are not subject to the requirements of Standard No. 207.

Standard No. 208 specifies occupant protection requirements based on vehicle type and seating position within the vehicle. Different requirements also apply depending on the GVWR of the vehicle. The discussion which follows is limited to vehicles with a GVWR greater than 10,000 pounds. As explained below, trucks are required to have, at a minimum, a lap belt at every designated seating position. As with Standard No. 207, Standard No. 208 does not apply to trailers. Therefore, the seats in the trailer portion of the response units are not required to have any type of safety belt at any seating position.

The requirements for trucks with a GVWR of 10,000 pounds or more are contained in section S4.3 of Standard No. 208. Vehicle manufacturers have a choice of two options for providing occupant crash protection in trucks manufactured on or after September 1, 1990. Option 1 requires vehicle manufacturers to provide an automatic protection system at all seating positions that meets the frontal and lateral crash protection and rollover requirements. Option 2 requires vehicle manufacturers to install lap or lap/shoulder belts at every seating position. If a manufacturer chooses to comply with Option 2, the lap belt or pelvic portion of a lap/shoulder belt must have either an emergency locking retractor or an automatic locking retractor.

Standard No. 209 sets forth strength, elongation, webbing width, durability, and other requirements for seat belt assemblies. This standard applies to all seat belt assemblies as separate items of motor vehicle equipment, regardless of whether the belts are installed as original equipment in a motor vehicle or sold as replacements. Thus, if seat belts are voluntarily installed at the seats in the trailer portion of the response units, the seat belts would be required to be comply with Standard No. 209.

Standard No. 210 establishes strength and location requirements for seat belt anchorages installed in vehicles, where seat belts are required by Standard No. 208. Therefore, anchorages are required for the lap belts in the tractor, but are not required in the trailer.

Although all of the safety standards cited in this letter do not apply to each seating position in your proposed emergency response unit, the agency nevertheless encourages additional consideration and application of those performance requirements that are appropriate to a safe design.

I hope you find this information helpful. If you have any other questions, please contact Mary Versailles of my staff at this address or by phone at (202) 366-2992.

Sincerely,

John Womack Acting Chief Counsel

ref:VSA#207#208#209#210 D:3/17/94