The purpose of this study is to test if the newly-developed Dabir alternating pressure (AP) overlay could be beneficial to preventing skin damage during daily activities, such as lying in bed. Specifically, the study is being done to test if the Dabir AP overlay could be used to increase skin tolerance when lying in bed for an extended period of time (40 minutes), including reducing pressure and increasing skin blood flow (amount of blood supply to oxygen and nutrients to skin) as compared to regular operation room (OR) overlay.