NotTaR of Television Sets : Should I be worried about X-ray exposure..  
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Should I be worried about X-ray exposure while servicing a TV or monitor?

The only source of X-rays in a modern TV or monitor is from the CRT. X-rays are generated when a high velocity electron beam strikes a heavy metal target. For anything you are likely to encounter, this can only happen in a vacuum - thus inside the CRT. The higher the voltage, the greater the velocity and potential danger. Really old TVs (prior to around 1975) may still have HV rectifier and regulator tubes - other sources of X-rays. However, modern TVs and monitors implement these functions with solid state components.

The thick front CRT faceplate protects users adequately but there may be some emission from the thinner sides. At 25-30 kV (quite low as X-ray energies go) X-rays will be stopped by almost any metal so what you have to worry about is where there are no shields.

Other than lowering the brightness (or high voltage!), there isn't anything you can do to reduce X-ray emission from the front of the monitor. Any sort of add-on screen (grounded or otherwise) unless it is made of thick leaded glass, will have no significant effect on X-rays. If you are still concerned, sit farther away.

However, realistically, there is very little danger. I would not worry about exposure unless you plan to be sitting for hours on the sides, behind, or under the TV or monitor - with a picture (there will be none if the screen is black).

It is interesting that even those 1.5" Watchman and .5" camcorder viewfinder CRTs have X-ray warning labels even though the high voltage used with these isn't anywhere near high enough to be of any concern!