In message <[email protected]>, dated Wed, 4 Apr 2007, "Barker, Neil" <[email protected]> writes:
>I think the real issue here is a result of the interpretation of the >words 'mechanically separable' in the RoHS Directive. Yes. >Many seem to consider that abrasion is a form of mechanical separation >that could remove as little as the surface layer alone. How about laser ablation? That can remove the coating one molecule at a time. It seems doubtful that the drafting panel that wrote the Directive had such heroic measures in mind. But this is typical of Directives; the drafting panels tend to be composed of people who have little experience in writing what are in fact legal documents, plus another group who have that experience but know little about the industrial context in which the Directive will be applied. And the register of the language is too high. You need to get down to brass tacks, like 'By mechanically-separable we mean that the parts are held together by solder, screws, rivets, brass tacks, nuts and bolts or adhesives. We do not mean chemically or thermally bonded, or welded.' >The Trimite advice is based on it not being mechanically separable from >the base material, Well, it isn't, unless you deliberately use quite extreme measures. >and hence not being a significant proprotion of the total mass. The >answer depends on your interpretation. We have our own chemical and >metallurgical laboratory and some very experienced people who work in >it, and have conducted our own analysis on treated parts and concur >that it is in fact non-compliant. How did they come to that conclusion? It isn't experience in chemistry and metallurgy that counts, but skill in interpreting the unsatisfactory wording of the Directive. Has anyone studied the wording in languages other than English. The problem there is that the English text is usually taken as definitive, and all the others are translations from it. So if the English is below par, so will all the others be. I have no connection with Trimite. But badly written Directives make me despair. -- OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk There are benefits from being irrational - just ask the square root of 2. John Woodgate, J M Woodgate and Associates, Rayleigh, Essex 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/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: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________
