(The Trustees of Columbia University December 21, 1995)
Infrared heat lamps use low amounts of energy, have an ability to heat quickly, and are low cost. There are two types of infrared heat lights, gas powered and electric. Gas powered infrared lamps are usually used in commercial warehouses. They are quite heat intensive and must be positioned at least ten feet away from the source (person or area) to be heated. Electric infrared heat lamps are most often found in the home. They used to be more common, but with the advent of new types of bulbs that diffuse various levels of heat and colors, consumers have a wider selection to choose from and it’s rarer to see the infrared bulbs in use. The infrared bulbs seen most commonly these days are used in heat lamps in some bathrooms.
Twenty to thirty minutes is recommended as the suggested maximum exposure for most body applications of heat lamps. While the distance should be adjusted for personal comfort, the lamp should never be placed closer than 18 inches to the surface toward which it is directed. Temperatures sufficient to cause burns may occur from infrared lamps. Do not use near an infant, or sleeping or unconscious person. These electric lamps should also not be used by people with sensitive skin or poor blood circulation. Do not place the bulb directly over the exposed person unless a protective screen is placed between the lamp and the user. When in operation for extended periods, connect the lamp to a porcelin socket. Because of the radiant heat in the beam of these lamps, it should not be used close to combustible materials or materials adversely affected by drying action.
The effects of infrared radiation on humans are normally only of a purely thermal nature– meaning that they warm you! The potential hazards of infrared heat bulbs, lamps, and radiators are mainly to your skin and eyes. Because of the intense and radiant heat emitted, skin can burn rather quickly. However, any overheating or burning will be noticed fairly immediately because of a violet colored skin reaction, preventing any further damage because once you see your skin turn purple, you usually move away from the lamp’s rays! If a infrared radiator is touched, especially tubular quartz types, severe burns can result. Most of the tubular quartz radiators also have a high working pressure, which can be dangerous if they explode or break. If considering a quartz type radiator, look for a low-pressure model.
Your eyes are very susceptible to high-intensity short-wave infrared radiation. Long-term exposure to infrared radiation can permanently damage the eyes. Glass blowers and arc welders, for instance, who are exposed to large amounts of infrared irradiation over time, are susceptible to depigmentation of the iris and opacity of the aqueous humor, also known as “glass-blowers’ cataract.” Goggles with special infrared absorbing glass should be worn by people experiencing long-term exposure to infrared radiation. People with limited exposure for only short periods do not need to take extra precautions. Some medical practitioners, for example, use infrared heat lamps for their incubators and do not need to take special protective measures.
Since these lamps generate intense heat, and contain a significant amount of pressure, they can easily shatter. Protect people and surroundings by employing proper enclosures, shields, lenses, and screens. Finger marks and scratches from handling should also be avoided as it causes weakening of the bulb, and more frequent shattering.
Infrared Wave length: 7.5 x 10^-7 meters to 1 x 10^4 meters.
The discovery of this wave occurred because many early experiments searched for similarities between infrared energy and visible light. These were finally revealed when, in 1847, Armand Hipolyte, Luis Pizeau and Jean B. Foucault of France showed that infrared radiation produced interference patterns similar to those of visible light. Tungsten-filament lamps produce radiant heat instead of visible light. The filament, which is sealed in a gas filled bulb or quartz tube is heated by electricity and operated at a temperature of 4000 degrees F to produce infrared rays.
