General sauna concept is to heat the body by several degrees. The body attempts to reduce the temperature by relaxing blood vessels, driving blood to the surface, and by sweating. This has the effect of increasing circulation, and allowing detoxification through the skin. Repeated sauna use increases the efficiency of sweating.
FIR wavelength is too long to be perceived by the eyes, however, the body experiences its energy as a gentle radiant heat which can penetrate up to 1.5 inches (almost 4 cm) beneath the skin. FIR sauna is able to provide beneficial effects at much lower temperatures (usually 90F-130F) than regular sauna.
Gordon Medical uses a Heavenly Heat FIR Sauna. Heavenly Heat Saunas has been building Saunas for the chemically sensitive person since 1988.About FIR Sauna