What part of the windshield is known as the critical area?

The critical area of the windshield is defined as the portion that is cleaned by the windshield wiper system. This area is crucial for the driver's visibility, particularly during adverse weather conditions like rain or snow when the windshield wipers actively remove water and debris. Clear visibility in this region is essential for safe driving, as it allows the driver to see the road, other vehicles, and potential hazards without obstruction. The effectiveness of the windshield wiper system directly impacts safety, hence the importance of maintaining this area in good condition.

While tinted areas and sections with stark visibility can be important for various reasons, they do not play the same critical role in ensuring clear visibility as the part maintained by the wiper system. The entire windshield area certainly contributes to overall visibility but it is the specific region serviced by wipers that is designated as "critical" for safe driving conditions.