FIRs travel at the speed of light and do not need air to transmit heat, because they propagate even in an absolute vacuum. This means that they do not heat the air, but only the bodies on which they are radiated. Therefore, FIR radiation heating produces ideal conditions of comfort, without generating convective motion. The air is therefore cleaner and healthier, not creating a vicious circle of dust that dirties and carries disease. It is not too dry, does not encourage the development of mould, condensation, carbon dioxide (CO2), does not burn oxygen and produces heat free of noise, odours, smoke and soot build-up.