My professor friend at University of Missouri-Rolla says that in office environments (data center environments) the oxidation is probably not a problem.
"You're correct - an office environment would probably not oxidize the Cr(III) to Cr(VI)." So, for office equipment, trivalent chrome finishes may be a suitable replacement for hexavalent chrome with respect to meeting RoHS requirements. Jim _____________________ James L. Knighten, Ph.D. Teradata, a division of NCR http://www.ncr.com 17095 Via del Campo San Diego, CA 92127 tel: 858-485-2537 fax: 858-485-3788 From: [email protected] [mailto:[email protected]] On Behalf Of John Woodgate Sent: Wednesday, March 09, 2005 11:47 PM To: [email protected] Subject: Re: RoHS impact on zinc chromate finishes In article <[email protected]. com>, Knighten, Jim L <[email protected]> writes > The argument you get into is if it starts as trivalent does it stay > trivalent. I'd be quite surprised if it didn't. Hexavalent chromium is a VERY strong oxidizing agent, so oxidizing trivalent to hexavalent requires an even stronger one, otherwise the reaction would go the other way. But stranger things have happened. -- Regards, John Woodgate, OOO - Own Opinions Only. The good news is that nothing is compulsory. The bad news is that everything is prohibited. http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
