Far Infrared is radiant heat which we ourselves as human beings naturally emit. This is the same heat we feel from an environment warmed by the sun. It is completely natural and 100% safe.
Human & animal sense of comfort has evolved from radiant heat from the sun. Our skin naturally tans, reflects and prompts us to avoid the suns hottest waves in the hundreds to thousands of degrees Centigrade – called Middle and Near (or Medium and Shortwave) infrared. The waves we find most comfortable are those that are absorbed by our environment and radiated back in the tens of Degrees Centigrade – called Far (or Longwave) infrared.
Far Infrared is what our skin and common materials in our environment absorb and emit the most efficiently and 100% naturally.