Effects of Temperature on Hand Sanitizer Efficiency

In times of pandemic, hand sanitizers are one of the things that slow the spread of contagious disease. As they are readily available, they are stored at different temperatures because they might be used in different environments. It is important to understand what effects storage temperature has on hand sanitizer effectiveness in order to maximize its effectiveness. This research addresses the effect of varying temperatures on hand sanitizer effectiveness. In four separate trials, we applied hand sanitizer before and after touching a cell phone to expose our hands to microbes, then applied our hands to pre-poured sterile LB-agar plates. After 75 hours, we compared the number of surviving bacteria from before and after plates and generated a killing effectiveness value. This study was successful in finding the most effective temperature for 70% ethyl-alcohol-based sanitizers. Our results show that hand sanitizers are the least effective at temperatures above 107.27 °F and the most effective at 96.17 °F. Knowing the temperature range at which sanitizers are the most effective will help us better store the sanitizers to achieve their maximum effectiveness.