Riding along the road on a normal day, drivers don’t typically worry about their windshield. But what happens if they are in a crash, the vehicle rolled over or even if the airbag deployed. Would that windshield stay in place? The answer is yes, it should. But there are many factors that affect windshield safety.

First, a few basics about your windshield. It is made from laminated glass because it helps the glass stay in place in case of breakage as opposed to tempered glass which shatters upon impact. Some side windows are being made with laminated glass now also.

Structurally Secure

The windshield is an integral part of the safety restraint system in your car. It should help keep the roof from crushing in on you in a rollover, allow the airbags to deploy in the correct position to cushion passengers, and prevent you and your family from being ejected in a serious collision. Retaining passengers inside the vehicle during an accident is one of the strongest factors in decreasing fatalities.

The windshield provides a significant amount of strength to the structural support in the cabin of the vehicle, according to the Auto Glass Safety Council (AGSC). For instance, in a front end collision the windshield provides up to 45 percent of the structural integrity of the cabin of the vehicle and in a rollover, up to 60 percent. (To learn more about crash testing visit the Insurance Institute for Highway Safety which evaluates a vehicle’s crashworthiness with the help of five tests: moderate overlap front, small overlap front, side, roof strength and head restraints and seats.

Think about what would happen if your windshield was displaced. More than half the force of a collision would have to be absorbed by you because your windshield flew out in an accident. That shouldn’t happen if your windshield is installed properly.

Windshield Safety Statistics

Proper windshield installations are crucial to safety in the event of an auto accident, but there is little data available on faulty windshield installations and how often they occur. The National Highway Transportation Safety Administration (NHTSA), the agency that normally tracks automotive safety issues, does not track windshield retention or windshield safety in accidents.

Automotive expert Ben Kelley of the Center for Product Safety spoke about windshield safety at an industry meeting a few years back. “The role of the windshield in maintaining vehicle integrity has not really been addressed by NHTSA,” said Kelley.

While data is not widely available for windshields that did not maintain the proper bond in an accident, NHTSA does track fatalities and injuries by windshield ejection, according to a 2009 proposal for Federal Motor Vehicle Safety Standards for ejection mitigation. Though the proposal mainly focused on sidelites, the proposal cited that from 1997 through 2005 and estimated that 3,488 people were injured by ejection through windshields and 1,155 were killed.

Consumer advocate Ralph Nader called on the NHTSA in 2005 to issue a consumer advisory regarding windshield replacements (and also called on the agency to introduce roof crush standards).

“Inappropriate adhesive applications, shortened drive-away times and improper glass handling techniques are just a few of the dangerous shortcuts plaguing the auto glass replacement industry and resulting in an unknown number of weak windshield installations which will not even protect occupants from the first impact in the first half roll,” wrote Nader in his letter to the agency. “Furthermore, an incorrectly mounted windshield may not even be strong enough to withstand the impact of a passenger airbag, which is designed to fire into the windshield for proper positioning. If improperly installed, a replacement windshield can literally be blown out of its mounting by passenger airbag detonation.”

Proper Replacement and Installation is Key

If a windshield is replaced improperly the airbag on the passenger side can malfunction when it deploys. Or in a front overlap crash, the windshield could pop out from sheer impact. That’s what happened in 1999 Jon Fransway’s sister. He now works as an advocate for the safe replacement of windshields, and works with the AGSC, to make sure that what happened to his sister doesn’t happen to others.

When to Replace

You may not have to replace your windshield at all—repair may be an option. When you bought your vehicle, it came with a factory windshield sealed in” by factory robots. So if you do get damage to your windshield and it can be repaired that is your best bet.

Minor windshield damage is usually in the form of a chips or crack. A chip is commonly formed when a piece of debris hits the windshield. It can take the form of a star break, bulls-eye, partial bulls-eye, crack chip or pit. The size of the damage reveals whether or not it can be repaired. 

Many auto glass shops do repair and replacement, and some are repair only. Glass.com can help you find a company to assist with that repair. Glass.com can also help you find a reputable installer if a replacement is needed.