Having been on oxygen 24 hours a day for ten years, I am ordering some of your Maine Warmers BECAUSE-on electric heating pad directions and precautions it says “Do not use in the presence of oxygen”. This, I think, is because if the electric pad overheats and the sheets catch on fire, there may be sparks, and the oxygen might explode. Since I don’t wish this to happen to me, I never use electric heating pads or electric blankets (or get near candles or fires). I don’t think anyone has ever mentioned this to me, and doubt if many people know it.