What comprises the critical area of the windshield?

The critical area of the windshield is defined as the area of normal wiper sweep. This is because visibility is paramount for the safe operation of a vehicle, and the wipers are designed to clear this specific area effectively. The normal wiper sweep is where the wipers make contact and remove rain, debris, or snow, ensuring that the driver has an unobstructed view of the road ahead.

Focusing on this area is essential for inspections as any impairment or obstruction here can significantly increase the risk of accidents. Other areas of the windshield, such as the entire windshield or only the bottom section, do not account for this specific functionality of the wipers, which is why they are not considered the critical area. The side areas next to the mirrors also do not play a role in the wiper function and visibility in the same way the normal wiper sweep does. Thus, the designation of the critical area is specifically tied to the effectiveness of the windshield wiper system in maintaining clear visibility.