Roof Crush and Windshields

I found an interesting article regarding the role of the windshield in roof strength. This article appears to be a marketing material disguised as a press release. Regardless, it provides some information regarding how the windshield affects the strength of a vehicle’s roof in a rollover event. According to the article:

Fixing a damaged windshield is not an option. A damaged windshield can mean the difference between life and death in a rollover crash. In today’s vehicles made of lighter materials, the windshield helps support the roof and keeps the airbag inside the vehicle. Windshields not only keep insects and rain out, they are vital for passenger airbags to properly function to keep occupants in. If a vehicle with a cracked windshield is in a crash, the force of the passenger airbag deployment could break the windshield instead of protecting the passenger, who may hit the dashboard. During a rollover the roof would crush the driver and occupants.

Apparently glass companies are using information regarding a roof’s structural integrity as a way to solicit windshield business. The article above piqued my interest to see what else is out there. I found another marketing article making the same arguments as above. According to an article written by a glass marketing agent:

Your windshield is a major part of your vehicle’s Safety Restraint System (SRS) which is found in all vehicles to provide protection from serious injury and death in the event of an accident. The windshield of all vehicles provides a substantial portion of the structural integrity of the passenger compartment. Over the years, proper installation (as well as replacement) has become an extremely important aspect of the manufacturing of vehicles. It has become a precise science, as windshield safety and structural engineering has seen dramatic increases in expectations among manufacturers. This may come as somewhat of a surprise to some consumers. While windshield integrity has come under intense analysis and study by vehicle manufacturers, most car consumers really never even address this fact. When most drivers have to consider repair or replacement, it is normally do to aesthetic reasons, while the structural aspects of having an uncompromised windshield tend to go relatively unheard of or even ignored. So how important exactly is it to have a structurally sound windshield? According to the National Highway Traffic and Safety Administration (NHTSA), more than 30% of the 40,000 Americans killed in highway fatalities annually, die after either being ejected from the vehicle or critically injured during rollovers. Needless to say, the integrity of the windshield is a critical factor in both of these conditions. The National Glass Association (NGA) has reviewed these figures, and has made it clear that a “measurable percentage of those fatalities occur when an improperly replaced windshield does not remain firmly bonded to the vehicle during a crash.” These figures are even more telling when applied to rollover crashes. According to the NHTSA, rollover crashes account for a mere 3% of all collisions, while that same small percentage is responsible for 31% of total vehicular fatalities. The administration also explains how, in 2000, almost 10,000 vehicles were involved in fatal rollover crashes and that 84% of those accidents involved only one vehicle. In 2001, 54% of all single vehicle crash deaths occurred as a result of rollovers.

I have posted previously regarding roof crush here, here, and here. It is curious to me that we are depending on windshields to provide structural integrity in our vehicle roofs when we know that a windshield will typically deform, break, and/or evacuate the windshield during a rollover. It is important that a roof is strong enough to maintain a certain level of structural integrity with or without an uncompromised windshield.