The core feature of every Sundirect heater is the far infrared heating element. It works the same way as a classic stove being a body with higher temperature which transfers energy to a body with lower temperature through electromagnetic radiation. We mainly consider three different types of infrared: Near infrared, Medium-wave infrared and Far infrared. Normally Near infrared heaters operate at high filament temperatures above 1,800 °C, Medium-wave infrared heaters operate at filament temperatures of around 1,000 °C and Far infrared heaters operate at a much lower temperature of approx 80°C to 120°C. Due to this core advantage, the Far infrared technology is widely used in the Far infrared sauna, Infrared lamps and other appliances for health treatment systems as well as in the panel heaters like those supplied by SUNDIRECT. Because the heating elements are at a relatively low temperature, SUNDIRECT heaters do not yield emissions, dust, dirt, formaldehyde, toxic fumes from paint-coating, etc. This has made SUNDIRECT heaters very popular among people with severe allergies and multiple chemical sensitivity. Several studies have examined the use of far infrared heater in the treatment of chronic health problems, such as high blood pressure, congestive heart failure and rheumatoid arthritis, and found some evidence of benefit.