dave@lsuc.UUCP (David Sherman) (11/27/85)
We are just in the final stages of setting up a course on Accounting in the Law Office, taught by CAI, as part of the Ontario Bar Admission Course. Our students were informed today of the details. The course takes about 5-8 hours on-line (plus a few hours of workbook work away from the terminal). We have over 1,000 students who must take the course in December and January. The exam, which will be available in February, will be 1.5 hours and also taken on-line. All access is through standard ASCII terminals (Esprit Executive 10/102s, which are VT-100 emulators; they draw about 50 watts each). Some students in the course who are pregnant are now objecting that they do not want to use a video display terminal, because they believe it is dangerous and related to birth defects. I would like to convince them that this is not the case, particularly when we're talking about an exposure of 7-10 hours over three months. I recall this being discussed on the net some time ago. Does anyone have data or reports they can mail me or point me to, which can help allay these students' fears? Any quick replies would be greatly appreciated. David Sherman (my wife's pregnant, and *she* still logs in) The Law Society of Upper Canada Osgoode Hall Toronto, Canada M5H 2N6 (416) 947-3466
ark@alice.UucP (Andrew Koenig) (11/29/85)
> Some students in the course who are pregnant are now objecting > that they do not want to use a video display terminal, because > they believe it is dangerous and related to birth defects. > I would like to convince them that this is not the case, > particularly when we're talking about an exposure of 7-10 hours > over three months. If the students to not want to use terminals because they believe the terminals are harmful, then they are right! They DO believe the terminals are harmful! My experience has been that arguing that people's beliefs are unjustified usually does little toward changing those beliefs, even when the arguments are valid.
dsi@unccvax.UUCP (Dataspan Inc) (12/01/85)
I would casually approach the recalcitrant subject(s) about how much
regular television they watch. Strictly from the point of view of a
video engineer, I'd much rather sit in front of a VDT than my Conrac
5111/19 master monitor; although both devices meet the applicable Federal
DHHS/Canadian DOC requirements for X-radiation.
The accelerating voltage in your typical terminal is between 8 and 12
kv. Most CRT specification sheets have a "clause" in their warning that
states "shielding of this tube and its enclosure may be required when this
cathode ray tube is operated above 12 kV."
On the other hand, entertainment televisions typically have accelerating
voltages from 26 to 38 kV and occasionally more. At 38 kv, CRT's are usually
equipped with a bonded or T-band faceplate which has been treated to
attenuate the X-radiation generated at the aluminized "rear" of the CRT face.
The amount of harmful radiation produced is a direct (though not
proportional) function of the accelerating voltage and certain design
parameters within the CRT. Real medical X-rays start at (I think) an accel
potential of 80 kV.
Unless and until someone does a study which compares the number of
birth anomalies/pregnancy complications among (or even throughout the spectrum
of) TV viewers and non-TV viewers, I might suggest that a sedentary lifestyle
in front of the terminal, while pregnant, could be equally the cause as
minimal amounts of radiation from the VDT. Even if it were shown that
"heavy viewers" had the most problems, this still would not conclusively
prove that the CRT faceplate is the problem.
BUT, should you desire, there is a product made by Victoreen/Nuclear
Associates (I think, ask any medical X-ray supply house) called "Clear-PB"
which your local glass shop can cut up and put in front of the CRT faceplate.
A very thin sheet of this (1/4 inch) is probably all that is required.
David Anthony
DataSpan, Incorporated
P.S. I am NOT giving engineering advice here. The statements are simply
a matter of opinion.ac4@pucc-j (Tom Putnam) (12/02/85)
In article <938@lsuc.UUCP> dave@lsuc.UUCP (David Sherman) writes: >We are just in the final stages of setting up a course ... >... The course takes about 5-8 hours on-line >(plus a few hours of workbook work away from the terminal). >... >Some students in the course who are pregnant are now objecting >that they do not want to use a video display terminal, because >they believe it is dangerous and related to birth defects. > >Does anyone have data or reports they can mail me or point me to, >which can help allay these students' fears? The U.S. National Institute for Occupational Safety and Health has published a number of summaries of visual display terminal (VDT) health issues over the last 5 years. You can write to them at: NIOSH, Publications Disseminations, DTS 4676 Columbia Parkway Cincinnati, Ohio 45226 Attn: VDT (I suppose they might mail a copy of their summary to Toronto..??) Better yet, check with the Canadian Occupational Health authorities. You might also check your local library for the August 1981 issue of the Human Factors journal where some papers on the subject were published. In (very short) summary, the reports say: * No problem with radiation (x-ray, radio-frequency, microwave, ultrasound, ultraviolet, infrared, or visible). * There can be problems with ergonomics. NIOSH recommends (source: FDA Consumer, April 1981, p.13) - Workers should be able to adjust the height of their keyboard, screen, chair seat, and backrest; screen brightness and contrast; leg room; viewing distance; room lighting levels; and chair tension. - Screen glare should be controlled by using drapes or blinds on windows, hoods and glare shields over screens, and proper positioning of machines with respect to room lighting. - Workers should take rest breaks of at least 15 minutes every 2 hours. - Workers should undergo a complete eye exam before they begin wiorking with VDT's and limited exams periodically. Again quoting from FDA Consumer, April 1981: "... in 1979 radiation worries welled up again when four women who worked at VDT's in the classified advertising department of a Canadian newspaper had babies with birth defects. The provincial government checked all of the newspaper's VDT's but could find no levels of radiation that could account for the birth defects. Nevertheless, the results of these tests by NIOSH and Canadian health officials were not enough to relieve the growing concern among VDT workers that many health problems were being caused by radiation from their machines." It goes on to describe additional testing and additional results as I summarized above. Just thought you should be aware that the concern may be very close to home! -- Tom Putnam, Manager of User Services Purdue University Computing Center ARPANET: ac4@asc.Purdue.EDU BITNET: PUTNAMT@PURCCVM CSNET: ac4@purdue-asc-tn USENET: {decvax|harpo|ihnp4|inuxc|seismo|ucbvax}!pur-ee!pucc-j!ac4 USMAIL: Mathematical Sciences Bldg. West Lafayette, IN 47907 PHONE: 317/494-1787
mazlack@ernie.BERKELEY.EDU (Lawrence J. &) (12/05/85)
>>... >>Some students in the course who are pregnant are now objecting >>that they do not want to use a video display terminal, because >>they believe it is dangerous and related to birth defects. >> >>Does anyone have data or reports they can mail me or point me to, >>which can help allay these students' fears? > >The U.S. National Institute for Occupational Safety and Health has >published a number of summaries of visual display terminal (VDT) >health issues over the last 5 years. You can write to them at: > > NIOSH, Publications Disseminations, DTS > 4676 Columbia Parkway > Cincinnati, Ohio 45226 > Attn: VDT There is an article in COMPUTER DECISIONS, November, 19, 1985, which talks about this topic. Apparently, there was a Spanish study done with chicken embryos that found reproductive problems. The article goes on to quote a NIOSH representative (Barry Johnson): "I haven't seen a convincing study on reproductive problems and VDTs. There's a crying need for such a study to be undertaken and completed." Other people on the roundtable discussion also agreed that it was an open issue. They also agreed that a good, controlled study to support either side had yet to be done. I think that the previous studies centered on the effects on workers, not on their unborn. If you can't get a copy of COMPUTER DECISIONS (a trade magazine), E-mail me a physical address and I will send you a copy. However, I think that someone carrying a child would not be reassured by this article. ...Larry Mazlack MAZLACK@ERNIE.BERKELEY.EDU