Over 90 percent of the information we need to control the vehicle comes from what we see. Vision is the foundation of safe and secure driving.
Vision is a complex sense affected by a number of variables, many over which we have no control. Your vision inside the car is not only affected by physical limitations but by factors such as tinted windshields.
Just how much visibility do we have when looking through a windshield? A non-tinted windshield permits 89 percent of the perpendicular light to pass through. Since almost no modern vehicles have perpendicular windshields (the exceptions being Jeeps and other utility vehicles), the real-world windshield value in this area is more like 82 to 84 percent of the light. By law a windshield needs to pass only 70 percent of the light to meet safety standards and that is when measured through a perpendicular windshield.
Add to that armored glass, dirt, and you can limit your visibility a great deal.
Likewise, a clean windshield is vital for driving whether in day or night. Streaks and smears on windshields can produce extremely disorienting kaleidoscopic effects when lights shine on them at night. Make sure your windshield washers work, that your windshield wiper blades are clean and not old and worn out, and that the windshield wiper fluid container is kept filled.
Keeping the inside of the windshield clean is equally important. If you smoke or drive with someone who does, you should clean the inside of the windshield every other day. It’s absolutely amazing to do this chore and see how fast smoke residue builds up on the inside of the windshield.