How is the 4-inch tint below AS-1 measured?

The correct method for measuring the 4-inch tint below the AS-1 line is to use a meter that conforms to state law. In Hawaii, as in many states, specific regulations dictate the measurement of window tinting to ensure compliance with safety and visibility standards. This method is more precise and standardized compared to other options, as it relies on calibrated equipment designed to provide accurate measurements of tint levels, which can influence a driver’s visibility and safety.

Utilizing a meter ensures consistent results that align with legal requirements, avoiding human error that could occur with subjective measurements or visual inspections. Advances in technology permit inspectors to measure tint darkness evenly and reliably across different vehicles, thus maintaining uniform standards for vehicle compliance in Hawaii's automotive safety framework.