Mr. Michael E. Kastner
Director of Government Relations
National Truck Equipment Association
1350 New York Avenue, Suite 800
Washington, D.C. 20005-4797

Dear Mr. Kastner:

This responds to your letter asking three questions about NHTSA's March 14, 1995 final rule (60 FR 13639) converting English measurements in selected Federal motor vehicle safety standards to the metric system.

Your letter indicates that you believe that the March 1994 final rule's changes apply to all the standards and to Part 567, Certification. This impression is not correct. The final rule applies only to the standards specified in the final rule, not to all of NHTSA's regulations. In the future, NHTSA will undertake rulemaking to complete metrication of the standards and will provide guidance for metric conversion of the remaining standards at that time.

Your first question was: "Does this final rule in any way result in a requirement that the part 567 label have dual metric English measurements? Do current regulations allow dual measurements even if they are not yet required?"

Our answer is that the March 1995 final rule made no changes to Part 567 and dual measurements are not required on the label. If metrication is not specified for a particular safety standard or other NHTSA regulation, the manufacturer may voluntarily provide metric measurements. However, when a final rule specifying metric measurements for a NHTSA regulation is promulgated, measurements (metric or English) for that regulation must be provided in accordance with the final rule.

Your second question was: "Does the final rule require that metric measurements be listed first with the corresponding English measurement listed second?"

For the standards that were amended in the final rule, i.e., Standard No. 110, Tire selection and rims; Standard No. 120, Tire selection and rims for motor vehicles other than passenger cars; and Standard No. 126, Truck-camper loading, the metric measurements must be listed first. The requirement does not apply to other standards.

Your third question was: "What metric and English abbreviations are acceptable to NHTSA? Should the abbreviations be in the plural or singular form? Should any acceptable abbreviations be in all capital letters?" You ask about conversions made by the rule in Standard No. 126, and abbreviations used in Standard No. 120's ATruck Example@ label.

The conversions (and abbreviations) made in Standards Nos. 126 and 120 apply only to the respective standards and are not generally applicable to all the standards. In the March 1995 final rule, NHTSA made the following comment concerning Standard No. 126:

[T]here should be no ambiguity in the metric units of measurement on labels that provide safety information to consumers. If unfamiliar terms are spelled out instead of abbreviated, there is less ambiguity and confusion. Thus, NHTSA is ... specifying the units of measurement as "Liters" and "cubic meters," as proposed, rather than the abbreviations "L" and "M3." (See 60 FR at 13644).

The required use of "liters" and "cubic meters" applies only to Standard No. 126 and is not applicable to other standards.

As for the Truck Example label in S5.3 of Standard No. 120, the words "kilograms" and "pounds" should be spelled out, whereas AkiloPascals@ is abbreviated as "kPa" and Aper square inch@ is abbreviated as "psi." This requirement applies only to the Standard No. 120 label and is not applicable to other standards.

I hope this information is helpful. If you need any further information, please contact Dorothy Nakama of my staff at (202) 366-2992.


Samuel J. Dubbin Chief Counsel

cc: Mr. Harley Holt Director, Automotive Standards Recreation Vehicle Industry Association 1896 Preston White Drive Reston, VA 22090 ref:571 d:3/13/96