Epoxy sensitization occurs with overexposure to epoxy resin and hardener. Rashes are a common sign, but eyes, nose, throat, & lungs can also be affected. You may become sensitized to epoxy after several exposures, or just one. Everyone reacts differently, so proper personal protective equipment (PPE) is critical when working with or sanding epoxy. PPE includes an appropriate respirator, and protection for eyes, hands, skin, and clothing.