Interpretation ID: 19751.wkm

Mr. Barry McManus
Vice President
Klein Products, Inc.
Post Office Box 3700
Ontario, CA 91761

Dear Mr. McManus:

This responds to your letter of March 17, 1999, to Walter Myers of my staff and to your telephone conversation with Mr. George Soodoo of this agency on March 22, 1999. You asked whether one of the products your company produces, a trailer-mounted water tower called the Klein Porto-Tower® (KPT), is required to be equipped with an antilock brake system (ABS). The answer is no.

You stated that the KPT is a trailer-mounted water tank that is utilized at construction sites where it is elevated into position, then filled with water to supply water trucks and wagons working at the site. The KPT is always transported empty when being moved over the highway, and filled only at the job site. You advised Mr. Soodoo that the empty weight of the KPT is its gross vehicle weight rating (GVWR) of 20,000 pounds, that the vehicle is equipped with an axle system rated at 22,000 pounds, and that when filled with water, the KPT weighs approximately 120,000 pounds. Thus, it can only be transported while empty because the axle system is inadequate to support the KPT when filled with water, and the tires and brakes are not sized for such a load. You stated that you have been equipping your KPT with ABS, while your competitors have not, which puts you at a competitive disadvantage. Finally, you stated that in reviewing Federal Motor Vehicle Safety Standard (Standard) No. 121, Air brake systems (49 Code of Federal Regulations 571.121), you believe that the KPT is exempt from the ABS requirements of Standard No. 121 by virtue of paragraph S3(f).

Paragraph S3(f) of Standard No. 121 excludes from the requirements of the standard "any trailer that has an unloaded vehicle weight which is not less than 95 percent of its GVWR, . . ." Thus, since the GVWR and the empty weight of the KPT are the same, and since the KPT is filled only when being used at work sites and is always completely emptied before being transported, it is excluded from the requirements of Standard No. 121, including the ABS requirements, by virtue of paragraph S3(f).

I hope this information is helpful to you. Should you have any further questions or need additional information, feel free to contact Mr. Myers at this address, by telephone at (202) 366-2992, or by fax at (202) 366-3820.

Sincerely,
Frank Seales, Jr.
Chief Counsel
ref:121
d.4/7/99