Interpretation ID: aiam1006
428 Southland Boulevard
Louisville
Kentucky 40214;
Dear Mr. Monk: Dr. Brinegar asked that I review and respond to your letter of Decembe 23, 1972, regarding warning devices.; As you know from previous correspondence, the National Highway Traffi Safety Administration (NHTSA) issued a Notice of Proposed Rule Making on a standard for warning devices in November 1970. One of our major concerns in issuing this standard was the great variety of warning devices of all sizes, shapes, forms and configurations that were available to the motoring public. While many of these provided varying degrees of effectiveness, the great variety also created confusion and misunderstanding to the motoring public. Standardization of these devices was therefore of prime importance.; In response to this notice many comments, designs and recommendation were suggested for inclusion in the standard. All responses were carefully reviewed and evaluated before we issued the final rule in March 1972. Federal Motor Vehicle Safety Standard No. 125 represents an attempt to achieve a balance between many factors including shapes, size, cost, visibility, stability and weight. Since these triangle are designed for ultimate use in all kinds of vehicles, from passenger cars to heavy trucks, we had to be careful not to specify requirements that would put them beyond the reach of the average motoring public.; We are appreciative of your comments to the docket and your subsequen correspondence of the Department of Transportation, regarding the wind stability requirement of the device. Vehicles traveling at 70 mph do not create an effective wind velocity of 70 mph off the roadside. Research data shows that warning devices designed to withstand wind velocities of approximately 40 mph will be sufficient for the majority of wind conditions created by truck turbulence and atmospheric wind velocities without unnecessary penalties in weight and cost. However, Standard No. 125 will in no way restrict the manufacture and sale of devices with higher wind-resistance capabilities for special uses. These are *minimum* standards.; Again, we appreciate your interest in this aspect of motor vehicle safety. it is the ideas and opinions of concerned individuals, such as yourself, that enable us to ensure rules and regulations that are meaningful and worthwhile to the motoring public. Thank you for writing E.T. Driver, Director, Office of Operating Systems, Motor Vehicle Programs;