Illinois CDL Practice Exam

A driver should check their mirrors every 5 to 8 seconds to maintain awareness of their surroundings and ensure safety on the road. This interval allows for a consistent scan of the areas behind and alongside the vehicle without being overly distracting. Regularly checking mirrors helps drivers stay informed about other vehicles in their vicinity, including those that may be in blind spots, and it can assist in making timely decisions when it comes to lane changes, turns, or preparing to stop.

In contrast, checking mirrors every 2 to 3 seconds may lead to an increased risk of distraction, impairing the driver's ability to focus on the road ahead. Checking only when changing lanes would mean missing crucial information about traffic conditions or potential hazards, while only inspecting mirrors at the beginning of a trip neglects the dynamic nature of driving where conditions can constantly change. Therefore, the approach of every 5 to 8 seconds strikes an appropriate balance between vigilance and attention to driving.