Automotive gas has been crucial in helping reduce injuries sustained during road accidents. Much stronger and durable than standard glass used in the windows of houses, buildings and storefronts, automotive glass is manufactured differently to withstand extreme pressure and high impacts better.
A little bit of history
It was only in the turn of the 20th century that a discovery was made that would later change the way automobile manufacturers improved vehicle safety. Even then, the laminated glass used wasn’t able to adequately protect occupants during more severe collisions. As the world entered the 1930s, tempered glass began to be manufactured and was used on the side and rear windows of vehicles.
With the importance of vehicle safety becoming a bigger issue, innovator individuals began to hone current automotive glass to increase its strength. Soon, polyvinyl butyral (PVB) replaced collodian films in laminated glass and is still continued to be used to this day.
Types of automotive glass
Modern automobiles combine two types of safety glass, tempered and laminated. The first has no film but is manufactured by inducing compressive and tensile stress. This increases the strength of the glass and causes it to shatter rather than break into chunks on high impact.
In contradiction to tempered glass, laminated glass is a sandwich of three layers. The first is a sheet of glass on which is placed a layer of PVB. A second sheet of glass sandwiches the film and all three components are heated to fuse them together. When the glass breaks, the film prevents it from shattering and creates a spider web pattern.
The windshield is one of the most important glass components of a vehicle. Other than protecting occupants in the event of an accident, it supports and absorbs the weight of airbags. When bags inflate, they do so with high velocity that can injure occupants. The windshield, thus, reduces the force of the inflation.
Both laminated and tempered glass is used in applications other than automobile safety. Glass railings, tabletops, countertops and microwave ovens are a few examples.
Acrylic, a type of plastic is used in place of tempered glass in many areas including aquariums and greenhouses. Said to be 20 times more resistant to impact than tempered glass, it is, nevertheless, flammable so will never be used as safety glass in vehicles. Still, it deserves to be mentioned considering its increasingly widespread use in other applications that earlier relied on tempered glass.
Tempered and laminated glass will continue to be used as safety glass in automobiles until such time as another better component is developed. The standard is that laminated glass is installed as windshields and tempered glass as side and rear windows. This gives occupants in a car escape routes in the event of an accident if the doors are jammed.
What some automobile manufacturers have done is to use laminated glass on rear windows to increase safety. However, there a few issues with this as laminated glass can’t be broken so escape routes in the event of jammed doors are compromised. Still, this hasn’t stopped car makers from coming up with new ideas that allow them to use laminated glass on rear windows. Vehicles with sun roofs offer a benefit in the form of an added escape route so occupants can choose to break the side windows or the sun roof if the doors jam.