What is the minimum light transmittance for a tinted windshield if applied to the AS-1 portion?

The minimum light transmittance for a tinted windshield applied to the AS-1 portion is established to ensure adequate visibility and safety for drivers. The AS-1 portion is a specified area on the windshield that extends from the top, typically about 5 inches down or to a designated point where the driver's view is most critical.

For windshields, regulations dictate that the light transmittance must be no less than 70%. This standard is in place to reduce the risk of reduced visibility due to tinting, particularly in conditions of low light, such as during nighttime or adverse weather. Ensuring a high level of light transmittance in the AS-1 area helps maintain clarity and provides a safer driving experience by allowing enough natural light to pass through.

The other options suggest lesser values, which do not meet the regulations and safety standards set forth for windshield tinting. A minimum of 70% transmittance thus protects both the driver's visibility and overall road safety.