Reducing Facial Lacerations in Head-Windshield Impacts with Windshield Lubricants 851735
A laboratory sled test program was conducted to evaluate the effects of a lubricant on the inner surface of a windshield on occupant injury criteria and facial lacerations. These (5) tests simulated 19 km/h barrier impacts of a production vehicle with 2.29 - 0.95 - 2.29 mm windshield laminates. The lubricant in these tests was a 60,000 centistoke (0.06 m2/s) silicone fluid which was manually applied to the windshield prior to sled acceleration. Laceration levels were evaluated in terms of the number, length, and depth of cuts produced in the double-layer chamois skin head coverings on unbelted Hybrid III dummies. Laceration levels were reduced by two orders of magnitude from those experienced with uncoated windshields, though performance did not reach the zero laceration levels sometimes attained with Libby-Owens-Ford (LOF) and Securiflex laceration shield windshield treatments. However, of all the anti-lacerative treatments that were reviewed, the lubricant was the only one that was not based on permanent physical changes to the windshield design. Improvements were also noted in certain other dummy performance measures; HIC (Head Injury Criteria) was lowered by 20 percent and neck moment reduced by 65 percent. Additionally, it was found that values of neck moment correlate with the surface friction coefficients of the different windshield treatments. These findings suggest the potential for altering features of the head, neck, and upper torso kinematics by adjusting the frictional level of the inner surface of the windshield.