Which piece of equipment is NOT required on passenger cars by state law?

Air conditioning is not a requirement for passenger cars under state law. While other equipment, such as safety glass, windshield wipers, and parking lights, are mandated for safety and operational efficiency, air conditioning is considered a comfort feature rather than an essential component for the safe operation of a vehicle.

Safety glass ensures that windows resist shattering, providing protection for passengers. Windshield wipers are critical for maintaining visibility during inclement weather, and parking lights help signal the presence of a vehicle when parked, particularly in low-light conditions. Each of these components serves a specific purpose related to safety and regulation, highlighting the importance of having them on passenger vehicles. In contrast, air conditioning serves to enhance driver and passenger comfort, which is not a legal stipulation for vehicle operation.