Portable heaters and home heaters are common household appliances and more than likely in some shape or form in our own homes. These heaters emit infrared radiation that is not dangerous to us as humans but will have an effect on our skin with unsafe use.
Home heaters emit infrared radiation that helps to heat oneself during cold periods of time. These heaters convert electricity to infrared heat which is non-ionizing radiation, meaning it's not dangerous to human skin. Many use these in the shower to reduce fog, in rooms to heat up space for comfort, even in office spaces. However unsafe use of these heaters has caused a skin condition that is induced by overheating of your skin. This occurs when prolonged use at an unsafe distance is the case. For this reason, many heaters have a warning label to keep it at a safe distance from any material deemed combustible. It is also important to know that we as humans emit infrared heat, and absorb infrared heat which is completely natural, and the way we stay warm in our clothing.
These factors work together to build a reputable conclusion that infrared heaters are safe and will not harm us. If you are sensitive to heat there might be precautions but it is important that you know your limits. It is important to take away that these appliances must be used at the safe and recommended distance in order to avoid any skin conditions such as the "Erythema ab igne" previously mentioned.