• The electromagnetic spectrum is divided into three segments by wavelength, which is measured in microns (1/1,000,000 of a meter).

• 0.76 to 1.5 microns = near infrared

• 1.5 to 5.6 microns = middle infrared

• 5.6 to 1000 microns = far infrared

• This wavelength of light warms objects without warming the air between the source and the object (known as conversion).

• This radiant heat can also be called Infrared Energy (IR).

• Do not confuse this with UV radiation (sunburn) or atomic radiation (nuclear) - see the diagram above for where these types of light fall on the spectrum.

• Infrared waves are not visible to human eyes but can be seen by special instruments that translate infrared into colors that are visible to our eyes.

• The best example is the sun (80% of the sun's rays are infrared).

• Our atmosphere allows infrared rays in the 7 to 14 micron range to safely reach the earth's surface.

• When warmed, the earth radiates infrared rays with its peak output at 10 microns.

• The human body radiates infrared energy out through the skin at 3 to50 microns, with most around 9.4 microns.