Infrared light, also known as infrared radiation, is a type of light that exists outside of the visible spectrum. Although you cannot see this light, you can feel its heat, though you are unlikely to be burned. The electromagnetic spectrum includes all wavelengths of light, ranging from short wavelengths, high-energy gamma rays to very long wavelengths, low-energy radio waves. Only a small portion of the visible spectrum is visible.
You probably use infrared light several times a day in your home without even realising it. Infrared light is used by TV remote controls to change channels, infrared radiation is used by toasters to transmit heat, and lamps may contain incandescent bulbs, which emit approximately 95 percent of their electrical energy as infrared light.
Infrared lamps are used to heat bathrooms, keep foods warm, and keep small animals and reptiles warm. They frequently emit both visible and infrared light. Saunas, thermal imaging cameras, fiber-optic cables, closed-circuit TV systems, infrared astronomy, and meteorology all make use of infrared light.
In sufficient concentrations, all infrared, visible, or ultraviolet electromagnetic radiation can cause eye injury, but this is extremely rare. In order to cause harm, the infrared light must be extremely intense. Because infrared light is invisible, your eyes will not take protective measures such as blinking or closing when exposed to a high-intensity beam of infrared radiation.
Wear appropriate eye protection if you work with infrared lasers. Lasers and laser-containing instrument systems must meet specific safety standards, which vary depending on the hazard classification. To prevent injuries, certain lasers are required to have beam shutters or key-controlled interlocks.
All rooms with potentially dangerous lasers should have warning signs at each entry point. However, extra precautions are not required when operating devices with an infrared laser beam that cannot reach the user's eye, such as TV remote controls and laser printers.