Re: Xterminal (which one) summary

From: Joe Dellinger (joe@montebello.soest.hawaii.edu)
Date: Thu Jun 23 1994 - 04:12:07 CDT


In article <2u9ijk$qbk@geraldo.cc.utexas.edu> tbodine@utig.ig.utexas.edu writes:
>1. Is it true that 19 inch Color Monitors for Sun3's are flakey?

        Well, whatever you do, make sure you DON'T GET AN OLD HITACHI SUN3
MONITOR with a manufacturer's date of around Sept 1986 - Jan 1987!!! Those
things are _dangerous_. I suspect most of them have gone up by now, however,
so you're probably safe.

        I posted this to comp.risks a while back. (And as a result I
would occasionally hear from some random person "hey, you were right in
your comp.risks posting, our Sun 3 gassed our building the same way and
when we checked it WAS from the same batch!".)

> On June 18, 1990 I reported how the Hitachi monitor of my color Sun 3-110
> workstation had suddenly released enough irritating fumes to prompt the
> evacuation of our (extremely poorly ventilated) Stanford building the previous
> evening. Here is the promised followup...
>
> Stanford Health and Safety was quite concerned about the incident; there are
> a lot of Suns at Stanford, and the fumes were still powerful enough a day
> after the event that persons entering my office would develop a headache
> and watering eyes within a few minutes. People in our building naturally
> wanted to know what toxic chemicals they were being exposed to. Health and
> Safety wanted to know if this might happen again. (I wanted to know when I
> could use my office again.) The Sun front-office people that Health and Safety
> first contacted insisted that this failure mode was virtually unknown and it
> would almost certainly never recur. We were suspicious of this claim, since
> in our research group we owned only six Suns of that particular model, and
> mine was the _second_ monitor to fail this way within as many years. (The
> first one fortunately had failed when the building was empty and when the
> ventilation was working better, so Health and Safety didn't get called
> that time.)
>
> My posting to risks which appeared a few days later netted a handful of
> accounts about similar incidents, mostly in Europe. More importantly, it
> prompted an immediate response from more informed people within Sun [Health
> and Safety was still trying to beat past the outermost layer of bureaucracy
> by telephone with little success]. Sun quickly retrieved the offending
> monitor from Health and Safety (who had carted it off and stored it as toxic
> waste) and launched an investigation. Sun determined the part that failed was
> a capacitor in the high-voltage line. This caused the flyback transformer
> coils to overheat, which in turn caused "a small amount of the case material
> of the flyback transformer to burn". Sun asked Hitachi, who made the monitor,
> to investigate what was in the resulting smoke. The conclusion was "There were
> trace quantities of a number of chemicals in the smoke. We do not believe that
> a short exposure to the small amount of smoke emitted represents a hazard to
> the individuals involved."
>
> Sun helpfully included a copy of Hitachi's lab tests showing what they
> got when they burned some transformer casing in a test chamber. It showed
> 10 parts per million CO (with 100 the maximum allowed by the American
> Conference of Governmental Industrial Hygienists), 800 ppm CO2 (no limit),
> 2 ppm Formalin (3 max allowed), 1.2 ppm Toluene (150 max),
> 1.7 ppm Ethylbenzene (125 max), and 3.4 ppm Styrene (100 max).
> This seemed strange to me; if the smoke were so innocuous why did breathing
> the air in my office still make me sick more than a day after the event,
> despite my best attempts to dissipate the fumes? I wanted to know how big a
> sample Hitachi had burned, and how much air the resulting smoke had been
> diluted in!
>
> The contact person at Sun seemed a little annoyed that I still wasn't
> satisfied, and resignedly explained again and again that "parts per million"
> was independent of the air volume. It didn't matter what size room the Sun
> was in, how good the ventilation was, or how much transformer case burned.
> I pointed out that it was a good thing my sun hadn't been outside, or the
> entire Earth's atmosphere would be contaminated with 2/3 the legal limit for
> Formalin. Right? They promised to get back in touch with Hitachi.
>
> Three months later I got another letter. It had the same numbers (in ppm)
> as before, and again had no information about the volume of the test chamber
> or the amount of transformer casing material burned in the test. It further
> patiently explained "All of the measured smoke constituents are significantly
> below OSHA's established minimum exposure levels. Since the smoke examined in
> the analysis is of the same type as emitted during flyback transformer failures
> at Stanford, no significant concerns are raised by the monitor failures you
> experienced." I tried calling and asking for clarification again, got the same
> explanations about ppm being independent of air volume (why couldn't I
> understand such a simple concept?!). Finally I gave up (after all the smell
> was gone by this time and there seemed to be no ill aftereffects).
>
> The second letter did have some interesting new information, however.
> Previously we had been told our monitor failures were practically unique;
> the new letter stated that "When the flyback transformer failure was
> discovered the total failure rate per month attributable to the flyback
> capacitors was only .4 percent. After the process improvement, which was
> promptly implemented, the failure rate was reduced to .04 percent. Although
> the newer model is superior, the older model was within the range of
> reasonable failure. Sun recognizes the frustration and disappointment that
> you must have experienced as a result of two monitor failures. This is an
> extremely unusual occurence [sic] and one that Sun would like to avoid in
> the future."
>
> Was it unlucky? We had 6 monitors for 3 1/2 years; given Sun's stated rate of
> .4% per month, the chance of at least one failure was 1.-(1.-.004)^(12*3.5*6)
> = 64%. Having 2 failures instead of just 1 _was_ probably a little unlucky.
> Was our problem _unusual_? Probably yes; from reading between the lines it
> sounds like the problem only occurred with certain smaller-sized Hitachi
> monitors delivered around the same time ours were, Sept 1986 - Jan 1987. Our
> bad luck was in getting 6 monitors from this batch, and then keeping them
> in near constant use for several years.
>
> The letter continued "Sun is prepared therefore to replace, at no charge,
> the four monitors remaining in the Department of Geophysics ... for your
> understanding that the failure rates are negligible and that in any event,
> monitor failures are unlikely to pose future problems." Our research group
> took the deal. Not surprisingly, the Geophysics department at Stanford has
> had no more such incidents since the monitors were replaced (despite a
> significant expansion in the total number of Suns in the building).

        I have not heard about such problems with any other Sun monitors.
Just be very sure you don't use one of the "cursed" ones, should any yet
survive!

-- 
     /\    /\    /\/\/\/\/\/\/\.-.-.-.-.......___________
    /  \  /  \  /Hawaii Institute of Geophysics, Honolulu\/\/\.-.-....__
___/    \/    \/Joe Dellinger, Internet: joe@montebello.soest.hawaii.edu\/\.-.__
Soon to be relocating to the mid-continental tourist paradise of Tulsa, Oklahoma



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