Interpretation ID: aiam5399
Inc. 1850 M Street
N.W. Washington
D.C. 20036;
"Dear Mr. Inui: This responds to your letter asking about the tes conditions for the dynamic side impact test of Standard No. 214, 'Side Impact Protection.' I apologize for the delay in responding. The test conditions are set forth in S6 of the standard. S6.1 explains how to achieve 'test weight:' Test weight. Each passenger car is loaded to its unloaded vehicle weight, plus its rated cargo and luggage capacity, secured in the luggage area, plus the weight of the necessary anthropomorphic test dummies. Any added test equipment is located away from the impact areas in secured places in the vehicle. * * * You first ask whether the weight of the added test equipment inside the vehicle is added to the test weight, or whether parts of the vehicle (weighing the same as the 'added test equipment') are removed to keep the vehicle weight at the 'test weight.' The answer is that parts of the vehicle may be removed, but only as a last resort. A brief explanation of how NHTSA calculates test weight follows. Under S6.1, 'test weight' is comprised of the combined weight of the vehicle with all fluids, the cargo and luggage weight, the test dummies, and nothing more. The cargo and luggage weight is derived by subtracting from the gross vehicle weight rating specified by the manufacturer the combined weight of the vehicle, fluids, and 150 pounds for each seating position. There are subtractions and additions to the vehicle weight in preparation for the test. The fuel is replaced with Stoddard solvent, but only to approximately 93 percent of capacity, and all other fluids (oil, washer fluid, etc.) are drained. Thus, the vehicle is lightened by the weight of 7 percent of the fuel and all of the other fluids. However, the added weight of cameras and any other necessary (non-dummy) test equipment usually more than compensates for the fluid weight loss, and the vehicle generally is slightly heavier than the test weight. Therefore, other weight must be removed until the test weight is reestablished. Please note that NHTSA will remove parts of the vehicle to compensate for the weight of the test equipment only as a last resort. The agency will first remove cargo or luggage ballast. If still more weight must be removed (i.e., in the unlikely event that the weight of the test equipment exceeds the weight of the removable cargo and luggage) the agency will remove parts of the vehicle. This is only likely to occur in vehicles with very small cargo capacities, such as sports cars. In this event, NHTSA would remove only parts of the car that play no part in the side impact test (e.g. bumpers). You next ask about the 'vehicle test attitude' specifications of S6.2. By way of background, NHTSA determines the attitude of the vehicle in its 'as delivered' condition (i.e., the vehicle as received at the test site, filled to 100 percent of all fluid capacities and with all tires inflated to the manufacturer's specifications) and in its 'fully loaded condition,' under the vehicle test attitude specification of S6.2. Under S6.2, the vehicle's pretest attitude is equal to either the as delivered or the 'fully loaded attitude' or between the as delivered and the fully loaded attitude. You ask whether the term 'fully loaded attitude' means the attitude of the vehicle in the 'fully loaded condition.' The answer is yes. Moreover, S6.2 specifies that ' t he `fully loaded condition' is the test vehicle loaded in accordance with S6.1.' As mentioned in our response to your first question, S6.1 explains how to load the vehicle to achieve the test weight. You also ask whether the 'as delivered' left-to-right attitude must be maintained when adding test equipment. The answer is also found in S6.2's specification that ' t he pretest vehicle attitude is equal to either the as delivered or fully loaded attitude, or between the as delivered attitude and the fully loaded attitude.' This language describes a range of attitudes, including the left-to-right attitude, which the vehicle may be in at the time of the test. The vehicle must be capable of passing the test anywhere within the prescribed range. Therefore, when NHTSA tests a vehicle, the agency has leeway in maintaining the as delivered left-to-right attitude when adding test equipment. As long as the left-to-right attitude after adding equipment is somewhere between the attitude in the as delivered condition and the fully loaded condition, an acceptable pretest vehicle attitude will be achieved. Finally, I would like to note that NHTSA's Enforcement Office prepares updates to its laboratory test procedures on an as-required basis. The updates include rule changes and maintenance revisions. We project a maintenance update to the side impact test procedures (TP-214D-03) will be published within the next six months. During this update, issues addressed in this letter will be considered. I hope you find this information helpful. If you have any other questions, please contact Ms. Deirdre Fujita of my staff at (202) 366-2992. Sincerely, John G. Womack Acting Chief Counsel";