Helmets have been trusted to provide protection against head impacts for millennia and have become a universally promoted piece of safety equipment. Current helmet standards provided by NOCSAE, SNELL, and ASTM for football, ski, motorcycle, and other activities specify the requirements for critical impacts under varying conditions such as; temperature, impact location, and impact energy. However, most standards only minimally account for the effects of sub-critical collisions and the natural fatiguing processes experienced by a helmet during its use. Intuition suggests that these seasonal cycles and minor impacts attenuate the utility of protective headgear; however, a scientific inquiry into such effects could illuminate or invalidate this assumption. The working hypothesis of the research team under Professor Randal Ching and Irv Scher was that sub-critical impacts and seasonal cycling would diminish a helmet’s protective abilities (as measured by metrics such as peak linear acceleration and severity indices), and the goal was to illustrate that current standards and refurbishing methods need to account for these various effects of age and use. Accordingly, my research group designed a helmet drop tower to test a variety of different helmets (football, motorcycle, and ski) according to SNELL and NOCSAE standards, and used helmets were compared to their new counterparts. Direct comparisons between used and new helmets were used to evaluate the effects of age and minor impacts on helmets, the effectiveness of current standards at predicting the utility of helmets, and the expected lifetime of helmets under given conditions. As the first independent study of helmet performance in the state of Washington, this study could give vital feedback to helmet manufacturers, helmet standard foundations, and helmet users alike.