[net.followup] X-rays from CRTs and Monitors - Info Wanted

henry@utzoo.UUCP (Henry Spencer) (05/18/84)

The following quote is of interest:

	Measurements performed under normal VDT [video display terminal]
	operating conditions by the FDA and NIOSH have *never* shown X-ray
	emissions significantly above the natural background radiation to
	which we are all exposed.  In order for our laboratories to produce
	any higher levels of X-radiation, they had to resort to extreme
	conditions, including maximum misadjustments of both user and
	service controls, excessive line voltages, and intentionally induced
	component failure -- conditions which in some cases led to illegible
	video displays and permanent damage to the units.

	Based on our measurements of ionizing and non-ionizing radiation,
	we do not believe that VDTs should pose a radiation risk to those
	who operate them.

This is from Dr. John C. Villforth, Director of the Bureau of Radiological
Health at the FDA, writing in Byte (page 37, Dec 1982 issue).  The
emphasis on "never" is in the original.  Villforth is known for persistent
agitation for better radiation protection for dental X-ray machines, so he
can hardly be considered a "see no evil" type.
-- 
				Henry Spencer @ U of Toronto Zoology
				{allegra,ihnp4,linus,decvax}!utzoo!henry

pc@hplabsb.UUCP (Patricia Collins) (05/22/84)

	On a recent National Public Radio show, a scientist spoke
	on the radiation hazards of CRTs.  The radiation level from
	a PROPERLY ADJUSTED CRT is 2 orders of magnitude LOWER than
	the radiation from another human being (due to naturally
	occurring radiation from chemicals within human bodies).
	That, in turn was a couple of orders of magnitude lower than
	the amount of radiation received by the average person (per
	year) from the sun.

	Similar measurements should be available on X-ray dosages.

	My opinion is that the biggest hazard from sitting in front of
	a CRT/monitor all day is not from EMR (etc.).  I would be
	most concerned about the inactivity.  Our bodies need motion,
	exercise, and change to function optimally.  Although, it is
	possible to improve "productivity" at a CRT by putting in
	uninterrupted hours of concentrated thought/programming/data entry,
	our minds also benefit from short breaks.  (Refer to your
	Psych 101 text for details.)


	For further info:

	"Health Protection for Operators of VDTs/CRTs, NYCOSH, 32 Union Sq.,
	Rm. 404, NYC, NY  10003  ($1)

	G.W. Wolfe, "Ionizing Radiation and VDTs,"  Kilobaud Microcomputer,
	July 1981

	W.E. Murray, et al, "A Radiation and Industrial Hygiene Survey of
	Video Display Terminal Operations, Aug. 1981

	R.C. Peterson, et al. "Nonionizing Electromagnetic Radiation 
	Association with Video-Display Terminals"

					Patricia Collins
					hplabs