What is the requirement for the spacing of lamp centers for identification lamps?

The requirement for the spacing of lamp centers for identification lamps is that they must be positioned at least 6 inches but not more than 12 inches apart. This specification is crucial for ensuring visibility and functionality of these lamps. Identification lamps, which are typically used to indicate the width and height of a vehicle, must be spaced accurately to provide clear and effective identification to other motorists, particularly in low-light conditions. Proper spacing supports compliance with safety regulations and enhances overall road safety by reducing the risk of accidents due to misinterpretation of vehicle size.

Other options either suggest distances that do not meet the minimum or maximum requirements set forth in the regulations. For instance, less than 6 inches or more than 12 inches would decrease the effectiveness of the identification lamps, failing to adequately denote the vehicle's dimensions. Thus, adhering to the specified spacing range significantly contributes to roadway safety.