Testing of automotive glass is also customized, based on where an automaker intends to sell a vehicle. "When automakers know they'll sell the same vehicle in North America and in Europe, they'll ask us to match to the European standard," said Jose Martinez, Window Systems Engineer, Grupo Vitro/VVP Auto Glass, Inc., Mexico and U.S.A.

A major test addresses light transmission—how much light comes into the vehicle. In Europe, the requirement is set at 75%+, while in North America it's set at 70%+.

Likewise, a set of resistance tests—addressing glass breakage/penetration—is different in Europe and in North America. "Actually, the way the test is performed is different in Europe and in North America, so for glass to pass, it must test (correct) to both test methods," explained Martinez, adding, "It is a cost issue."

Testing to different standards also requires different processes, covering specific tooling and equipment (furnaces). The company's OEM glass operations complete all glass testing in-house at locales in Monterrey and Mexico City, Mexico.

As with any business venture, two-way communication with such customers as General Motors, Ford, DaimlerChrysler, Nissan, Volkswagen, and Freightliner saves time and money. "From the beginning, you usually know where the customer is going to sell the vehicle, so you can predict which tests will be required," Martinez said.