In relation to windshields, what defines the critical area?

The critical area of a windshield is defined as the area wiped by the wipers. This is important because it is the portion of the windshield that is essential for the driver’s visibility during adverse weather conditions, such as rain or snow. The wipers are designed to clear this area to ensure that the driver has a clear line of sight while driving. Therefore, any obstructions, damage, or defects in this area can significantly impair visibility and potentially increase the risk of accidents. Proper inspection and maintenance of the critical area are crucial for safety standards in vehicle operation.

The other areas mentioned do not have the same direct impact on visibility while driving. Sections that are not visible from the inside, those in the lower corner, or areas above the rearview mirror do not play a role in the immediate, critical visibility that the driver requires for safe driving.