This is an informative video from Sika (The manufacturer of the liquid rubber known as Urethane that I have used for 20 years), and it demonstrates in a very effective way the importance of proper products and procedures needed for a safe and proper windshield installation. When properly used and cured, the Urethane has a tensile strength of up to 800 psi, “FMVSS212 Wind-shield mounting standards”.
This video shows the force exerted on the windshield by the passenger side air bag in a front end collision. This demonstrates the importance of a properly installed windshield and the role it plays in the deployment of the passenger side air bag. The passenger side air bag uses the windshield as a back board as it explodes out of the dash, and if the windshield is not properly installed, the air bag wil not be directed towards the passenger. Also, the windshield is designed to keep the passengers in the vehicle in a collision up of to 30 miles an hour, “FMVSS208 Occupant crash protection standard”.
This crash test is a great example of how today’s cars are engineered to withstand front end collisions with energy absorbing crumple zones, and advanced passenger cabin structures including glass. When watching the video, take note how the pillar post and windshield frame on the ’59 Belair fold into the passenger cabin and the windshield flew out, compared to the ’09 Malibu where the passenger cabin stays intact. This is partially due to a properly bonded windshield that was engineered to transfer energy to the roof structure via the pillar post, “FMVSS212 Wind-shield mounting standards”. The windshield also helps support the roof in a roll over situation, “FMVSS216 Roof crush resistance standards”.