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Re: our list, telecine characters, and Perc.




Regarding Perc and Trichlor:

While I was at VTA, I found some publications from DOW Chemical on the 
supposed dangers of these two chemicals.  The articles were copyrighted, 
so I can only paraphrase.  In essence, their papers stated that the 
danger from these two substances was not from physical contact, nor even 
ingestion(!) -- it was breathing them, due to their oxygen-replacing 
action in the lungs.  1:1:1 was considered dangerous at a level of 
10,000ppm, while perc was dangerous at 6,000ppm, a considerably lower level
of vapor concentration.  The papers actually said there was no carcinogenic 
property to either chemical, which my gut told me to regard with some 
suspicion, even though DOW is one of the manufacturers of these chemicals.
With regard to Perc, while not as deadly as quickly as, say, Hydrogen 
Sulfide (a true Class 4 chemical), it's really far more dangerous than 
what we're used to using, and I'm glad to be independent and not have to 
handle it myself!  Nasty stuff!  I believe Lipsner Smith says to allow 2 
or 3 minutes, I can't recall exactly which, before opening the doors of the 
CF3000 after cleaning a roll of film when using Perc.

The other thing regarding this matter is the CF3000 Lipsner Smith Film 
Cleaner, which you may or may not have in your facility.  Despite the 
claims of using only 5 gallons/year with the recycling method, again, 
while at VTA, it seemed to be losing fluid at a considerably faster rate 
using Trichlor.  (This was *after* a leak in one of the vapor reclaiming 
tanks was discovered and fixed.  We could smell it, but we couldn't really 
see a leak.)  This means that you will have to deal with handling the 
chemicals to refill a lot more often than you might think.  Another point 
here - the design of said defective reclaiming tank left a lot to be desired:
it *appeared* to be two of the old woven cotton filter metal casings from the 
CF2000 with the open ends bolted together, with no fitted ends, no "O" 
rings, no gaskets.  Scary, considering the vapors are supposedly the 
dangerous part!  Hopefully, this part of the machine will undergo some 
redesign.
 
Ralph Edwards