A relatively new method for retaining fixed glass in these vehicles is with the use of a urethane sealant. This material is used because of its ability to furnish the necessary strength by providing the required glass retention to comply with Federal Motor Vehicle Safety Standard No. 212. Utilizing the glass in this manner improves the overall body structural integrity.
“An intent of FMVSS No. 212 is to reduce occupant ejection allowed by windshield bond separation. Windshield bond separation rather than penetration through the glazing is the most common ejection route for fatally injured occupants who are ejected through the windshield.” (See Ref. 1.)
For this reason, vehicle manufacturers that utilize a urethane bonding system for glass retention, require that any replacement glass be installed with the same type of sealant that is applied during assembly of the vehicle. This urethane bonding system is known to be used on vehicles produced by General Motors, Ford Motor Company, Chrysler Corporation, Toyota, and a number of other manufacturers. (Specific applications are usually listed in their respective shop manuals.)
Urethane can easily be recognized, after glass removal because it is harder and less elastic than other installation materials. Installation procedures are similar and are being implemented by most well-equipped glass installation shops. No significant, additional material cost or labor is involved. In those cases when any doubt of the material exists, it should be resolved in the favor of the utilization of urethane as the glass retention adhesive.
It is extremely importatit when repairs are made to a collision damaged vehicle that any replacement glass, requiring a urethane sealant, be installed with the same type of sealant in order to insure the safety and structural integrity of the automobile. The sealant should be of a quality to assure the windshield retention per FMVSS No. 212.