Interpretation ID: nht79-4.15

DATE: 03/07/79

FROM: AUTHOR UNAVAILABLE; Frank Berndt; NHTSA

TO: Truck Trailer Manufacturers Association

TITLE: FMVSR INTERPRETATION

TEXT: We regret the delay in responding to your April 18, 1978, letter criticizing the National Highway Traffic Safety Administration's (NHTSA) interpretation concerning the responsibility of a manufacturer for ensuring that its vehicles will not be overloaded when transporting materials for which they are designed. In that interpretation, the agency indicated that a vehicle whose tank cargo volume is of such size that it misrepresents the assigned GVWR and GAWR values of that vehicle, thus, inviting overloading might be considered to have a safety related defect. Please permit me to qualify the interpretation in the light of your criticism.

The NHTSA realizes that overloading is a problem created for the most part by the operator of a vehicle. Accordingly, it is not intended by the agency's interpretation or regulations to hold a vehicle manufacturer responsible for every situation in which a vehicle is overloaded. Most any type truck can be overloaded by the user. An operator should be aware of this possibility, however, given the amount of space on that vehicle on which cargo can be loaded and the broad range of cargo that can be transported by that vehicle. If a truck designed for the transportation of one specific cargo were misused by the operator to transport another type of cargo not intended by the vehicle manufacturer, then any resultant overloading would be the responsibility of the operator not of the manufacturer. However, when a vehicle designed to transport a specific cargo can be overloaded when filled to its capacity with that cargo, the NHTSA has determined this to be a problem created by the vehicle manufacturer and would consider taking action against a manufacturer to correct the problem. This agency's interpretation that a vehicle be able to safely transport its intended design cargo when fully loaded is an objective and unambiguous requirement and simply places the burden upon a manufacturer to ensure that the design cargo does not exceed the GAWR and GVWR.

Specifically we are concerned that a tank of fixed volumetric capacity could be loaded to exceed the vehicle's GAWR and GVWR values when filled with a commodity of design density simply because of the tank being too large.

When there is reason to believe that the density of a cargo likely to be transported could present a vehicle overloading problem, the manufacturer has a duty to provide a warning and information as a precaution in averting the potential hazard. The NHTSA does not object to the practice of partial loading of tankers and tank compartments for remaining within safe loading limits provided guidelines are furnished by manufacturers for performing approved loading operations. Prescribed precautions hopefully will counteract any tendency to perceive volume as the load limiting criterion. We would agree that loading information as contained in your enclosure would be a satisfactory means of conveying safety information and could be referenced on a conspicuous vehicle label.

SINCERELY,

Truck Trailer Manufacturers Association

April 18, 1978

Joseph J.-Levin, Jr. Chief Counsel Department of Transportation National Highway Traffic Safety Administration

Gentlemen:

This is a response to your letter of July 1, 1977, your file No. NOA-30, written to Mr. Jerry McNeil of American Trailers (ref. other correspondence on the same subject), regarding the act of a user's exceeding a vehicle's GVWR possibly being considered a safety defect.

We take strong exception to this interpretation for several reasons:

(1) Your interpretation assumes a user to be either not knowledgeable or dishonest by overloading a tank with a commodity with too high a density for the tanks total capacity. We must design with the premise that a user is knowledgeable and honest.

(2) Your interpretation excuses overloading of certain types of vehicles but not volumetric type. Whereas overloading is the responsibility of the user, any type vehicle can be intentionally or naively overloaded.

(3) Your interpretation, if strictly enforced, would eliminate the use of one vehicle for more than one density commodity at great expense to the consumer. However, all State and Federal weight laws are written using weight in pounds; there is no reference to density.

(4) Your interpretation is so general that it defies any definitive objective evaluation. It would be impossible to clearly define literally the thousands of load types or combinations of load types that are possible. Your interpretation would hold one party responsible for another party's violation of the law. We doubt that this would hold up in court.

Partial loading of tank vehicles has been a general practice of our industry for over 50 years.

It is done safely and for good reason.

The most common example of partially loaded tanks is the typical 9000 gallon aluminum gasoline tank with 5 compartments. The tank weighs approximately 10,000 pounds and the typical GVWR of a vehicle such as this would be 70,000 lbs. Full loading with gasoline at 6.1 lb./gallon would provide a gross vehicle weight of 64,900 pounds (54,900 lb. of product & 10,000 lb. of tank), well within the vehicle's GVWR.

Partial loading with home heating oil at 7.2 lbs/gallon is achieved by leaving the third tank compartment empty (see attached sketch), reducing the total volume capacity to 7625 gallons and maintaining a gross vehicle weight of 64,900 lbs. - again 54,900 lb. product, 10,000 lbs. of tank.

This double purpose tank is versatile, practical, safe and very common. We estimate the total fleet of 9000 gallons tank to be about 3000 units. There are also many more gasoline tank both larger and smaller than 9000 gallons.

If we understand you correctly, your interpretation is that if an operator loads home heating oil into all five compartments overloading the vehicle and exceeding the gross vehicle rate rating (GVWR), the manufacturer may be held liable for a safety defect and be subject to a recall campaign. If, however, an operator loads a flatbed or van trailer with automobile batteries and causes the same overload and subsequent safety problem, this would not be considered a safety defect. It is just as likely that a volumetric type vehicle body, such as a tank grain trailer or dump truck, etc., could be incorrectly loaded as it is for flatbed trailer.

For instance, a grain trailer is sized to handle a safe legal payload of the lighter grains and have the sides high enough to safely retain the product while in transit. If an operator heaps a load of the heaviest grains he will more than likely exceed not only the GVWR, but also the local state weight laws.

If your interpretation is enforced it would require that we manufacture vehicles for single purpose use which would cause a tremendous duplication of equipment and would be a waste of our natural resources and energy.

You can see that a manufacturer has no control over the loading practices used on his equipment after the vehicle leaves his premises.

We would appreciate very much reconsideration of your position and would welcome the opportunity to make more detailed presentations of our position if you have further questions.

Charles J. Calvin President

PETROLEUM TANK TRAILER

A typical 9000 gallon aluminum petroleum tank trailer conforms to MC 306 and is designed to carry gasoline and/or fuel oil.

(Graphics omitted) Weight Summary Tank weight 10,000 lb GVW Trailer 64,900 lb Payload 54,900 Tractor weight 15,100 GCW 80,000lb

Loading Schedule Compartments Gasoline Fuel Oil Fuel Oil at 6.1 lb/gal at 7.17 lb/gal at 7.17 lb/gal 1 2000 gal 2000 gal 2000 gal 2 1875 gal 1875 gal 1875 gal 3 1350 gal EMPTY 1350 gal 4 1875 gal 1875 gal 1875 gal 5 2000 gal 2000 gal 2000 gal Total payload volume 9000 gal 7625 gal 9000 gal Total payload & trailer 64,900 lb 64,900 lb 74,530 lb GVWR 70,000 lb 70,000 lb 70,000 lb

Improperly loaded trailer results in a loaded weight which exceeds the GVWR by 4530 lb.