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- Path: sparky!uunet!ogicse!uwm.edu!spool.mu.edu!umn.edu!barracuda!aaron
- From: aaron@barracuda.micro.umn.edu (Aaron C. Sawdey)
- Newsgroups: sci.electronics
- Subject: Re: Question on BeO , Be Cu
- Message-ID: <1992Nov8.181413.6384@news2.cis.umn.edu>
- Date: 8 Nov 92 18:14:13 GMT
- Article-I.D.: news2.1992Nov8.181413.6384
- References: <118.UUL1.3#666@vortex.COM> <1992Nov4.154848.3915@dtint.uucp> <40689@sdcc12.ucsd.edu> <40690@sdcc12.ucsd.edu>
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- Organization: University of Minnesota, Minneapolis: Under Grad Workstation Lab.
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- In <40690@sdcc12.ucsd.edu> ikoutsel@sdcc3.ucsd.edu (Ioannis Koutselas) writes:
-
- >Hello. I would like
- >to ask if someone kwows the minimum levels of exposure to BeO
- >and BeCu dust ? I have accidentally (kind of) used BeCU
- >to make springs for an experiment, without ever knowing that
- >the dust of Be is also carcinogenic. Is it that there is
- >a minimum exposure level ?
-
- 66th ('85-'86) CRC Handbook of Physics and Chemistry says this about Be:
-
- "Exposure to beryllium dust in air should be limited to 2ug/M^3 (8-hr
- time-weighted average -- 40-hr week), with a ceiling concentration
- of 5ug/M^3. A maximum peak above the acceptable ceiling concentration
- for an 8-hr shift is 25ug/M^3 for a maximum duration of 30 min. These
- values are being reviewed and studied."
-
- The stuff's pretty toxic, in other words. My first exposure to this was
- a lecture about why you should leave immediately if you break the tube
- of an Argon-Ion laser (other than the fact that they cost $10k+): the
- heated anode in the tube contains beryllium to improve its electron-
- emission properties. (We had a tube that didn't work -- we rejuvenated
- it by passing a very large (10x normal) current through the anode
- heater to drive Be out to the surface of the electrode -- worked great,
- we got 5.5W out of an ancient 5W laser (water-cooled)).
-
- >Are the effects of Be chronic ? In other words do Be
- >atoms mutilate cells continuously in the human organism
- >or is there a decay in the action ? Can our body
- >get rid of Be in some way ?
-
- Hmmm. Any answers to this one? Perhaps a re-post to some more appropriate
- group?
-