|MadSci Network: Medicine|
Sometimes this question is asked because of a concern about "radiation" from the TV set, and sometimes it is asked because of concern about eye strain and/or bad posture.
Children should probably sit as far away as is comfortable, probably at least 5 feet away. However, if your child demands to sit very close to the TV, it could signal a visual problem. Check to see if the child is squinting his/her eyes or if they complain of eyestrain, double vision, or color vision perception problems. If there is a problem, it can usually be corrected with glasses or contact lenses. Some may require vision therapy. In any case, you should have your child routinely examined by an optometrist.
Televisions and other devices which makes an image is a similar way (like most computer monitors and video games) produce low levels of many different kinds of radiation. The types of radiation produced include everything from static fields to X-rays.
The actual radiation levels produced by TVs (and computer monitors) are all far below both U.S. and international standards. Sitting to close might hurt your eyes, but it won't be a "radiation" effect.
Studies in this area are summarized in a paper published by the Institute of Electrical and Electronics Engineers (IEEE) in 1997. The paper, BIOLOGICAL AND HEALTH EFFECTS OF ELECTRIC AND MAGNETIC FIELDS FROM VIDEO DISPLAY TERMINALS is available on an IEEE website.
I hope this helps.
Kenton McWilliams (Graduate Student, Optometry)
John Moulder (Radiation Biologist)
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