Windshield Replacement Could Cause Passenger Side Airbag Failure
When an impact occurs, the passenger side airbag is designed to first bounce off of the windshield before bouncing back and cushioning the passenger. The problem that could happen if a windshield has just been replaced is that the adhesive used to bond the windshield to the car could fail. If the adhesive doesn’t hold the windshield in place, the windshield will pop out when the passenger airbag deploys. The airbag will then continue forward and deflate on the hood of the car. The passenger’s face will collide with the metal airbag box located in the dashboard rather than a soft pillow of air as expected.
Why would an adhesive fail? Most of the urethane adhesives used by windshield replacement companies are designed to pass federal motor vehicle safety standards and create a strong bond to prevent such an occurrence. However they can take up to 24 or more hours to cure sufficiently. So even if a federally approved, crash tested adhesive is used, if an accident occurs while the adhesive is still wet, the windshield could pop out causing the passenger side airbag to fail.
Most reputable auto glass replacement companies will calculate the estimated time it will take before the adhesive has cured sufficiently. This calculation is called the “safe drive away time” and is based on the temperature and humidity at the time of the windshield replacement. This is most critical for cars equipped with passenger side airbags. For those without passenger airbags, the amount of cure time before crashworthiness is restored is less. In general, automotive urethane will cure faster in warmer and wetter conditions such as a humid summer day versus cold and dry conditions such as winter time.
That’s not to say the car is unusable for up to 24 hours. Many companies will explain the safe drive away time and offer to use a chemical cure or quick cure urethane instead. These adhesives are chemically activated to cure within an hour offering the car owner a one hour safe drive away time for cars equipped with passenger side airbags. While more expensive, the price of convenience often is a motivating factor. Like their slower curing counterparts, these urethanes are designed to meet or exceed all federally mandated safety standards and crash tests, they simply reach the desired crashworthiness faster.
When replacing a windshield on a car with or without passenger side airbags, it is critical to understand the safety issues and follow the recommended safe drive away schedule. Before the job is even started, ask the technician when the car will be safe to drive and if that time frame is not acceptable, ask for (and be willing to pay extra for) an upgrade to a fast cure or chemical cure adhesive.
