| Autor: |
Saczalski, Kenneth J., West, Mark N., Saczalski, Todd K., Sauer, Bruce K., Traudes, Daniel |
| Předmět: |
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| Zdroj: |
International Sampe Technical Conference; 2016, p1206-1221, 16p |
| Abstrakt: |
An important safety factor required for minimizing the severity of repetitive head impact forces and concussions in football is the need for reliable and consistent performance levels of the energy absorbing capacity of football helmet padding materials, such as resilient foams and TPU honeycomb materials. Unfortunately, helmet energy absorbing material performance levels are not currently assessed under certain normal use environmental conditions such as practice and game situations involving high humidity above 90 percent with high temperature, which can adversely affect the ultimate performance of a helmet and the protection to the player. The current football helmet performance test certification procedure, the NOCSAE, only requires testing at ambient conditions and a high temperature, but only with test humidity at the range of a 25% to 75% level. In this study, the energy absorbing capacity of elastomeric foams and TPU materials used in a popular Youth football helmet, approved for use in Pop Warner, were quasistatically tested at both ambient conditions and with the padding soaked overnight in an environmental chamber set to a "high humidity" of 95% and a "high temperature" of 46 degrees Celsius. The front, side and rear helmet padding materials were compressed at a load rate of 1.27 cm per second to approximately 67% of thickness by using a servo-hydraulic load-stroke actuation device. The results showed that the padding from the newly purchased Youth helmet were extremely sensitive to the high humidity soak conditions and resulted in approximately a 50% loss in energy absorbing (EA) capacity for a given amount of crush in the front, side and rear pads. The result of this pad "softening" is that it takes more deformation to absorb a given amount of impact energy in a limited helmet crush space and thus becomes easier for the pads to "bottom-out", leading to a dangerous case of higher impact load transfer to the head and brain of the athlete. These results suggest the need for additional study and improvement of EA padding. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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