We store HASL and ENIG for 3 years, while Silver and tin are 1 year. Jeffrey Bush Director, Quality Assurance and Technical Support VERMONT CIRCUITS INCORPORATED 76 Technology Drive - POB 1890 Brattleboro, Vermont 05302 Voice - 802.257.4571 ext 21 Fax - 802.257.0011 <http://www.vtcircuits.com/> -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Phil Nutting Sent: Friday, April 28, 2006 9:03 AM To: [log in to unmask] Subject: [TN] Shelf life of circuit board plating Good Friday Morning All, This topic may have been previously discussed, but let me try to phrase my "problem" completely so the answer can be simpler. I have a board vendor (Fab house) stating that for my ENIG boards the plating only has a 6 month shelf life if the package is opened. Did I miss something here? I thought Gold doesn't tarnish. If this is true, then Immersion Tin, Immersion Silver and ENIG all have storage issues. OK, so I open a sealed package and take out half of the boards in the package. I may not need the rest of the boards for many months. So how do I protect the unused boards? Should I vacuum seal them? Add a desiccant? If I add a desiccant, are there different desiccants which might damage the boards? I'm sure I'll have more questions right after I send this. Phil --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------