Interpretation ID: 18265-a.wkm

Mr. Alan S. Greenberg
President
Worldwide Machinery
16-31 East Freeway
Channelview, TX 77530

Dear Mr. Greenberg:

Reference is made to your letter to this office in which you enclosed a picture of your Standing Water Tank and argured that it is exempt from the antilock brake system, or ABS, requirements of Federal Motor Vehicle Safety Standard (Standard) No. 121, Air brake systems (49 Code of Federal Regulations (CFR) 571.121). You stated that your trailer is exempt by virtue of "Exception (f)" of the standard.

We assume that you are referring to paragraph S3(f) of Standard No. 121, which excludes from application of the standard "[A]ny trailer that has an unloaded vehicle weight which is not less than 95 percent of its GVWR." The term "gross vehicle weight rating," or GVWR, is defined in 49 CFR 571.3(a) as "[T]he value specified by the manufacturer as the loaded weight of a single vehicle" (emphasis added). Therefore, the loaded weight of your tank/trailer assembly would presumably be its weight when filled with water to its nominal tank capacity.

Before we can determine whether your water tank/trailer assembly meets the exclusion of paragraph S3(f), we must know the GVWR that you have assigned to it as well as its empty weight. Is your water tank transported either partially or fully loaded with water, or is it transported empty? If transported empty, what feature in the tank or trailer design prevents a user from transporting the tank fully loaded with water? Is your standing water tank used for other purposes, such as to provide potable water in disaster areas? If so, is it transported to such sites either partially or fully loaded with water?

We have tried repeatedly to contact you by telephone to obtain this information, but have been unable to do so. If you will provide us the information requested above, we will expedite a response to you so that this matter can be resolved. My staff point of contact is Walter Myers, who can be reached 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.4/8/99