Immersion Silver and Immersion Tin both tarnish in the presence of Sulphides and Chlorides, and H2S and Cl are both a couple of our main target gases for our gas detection equipment.  It's a black tarnish and the PCB fabricator assured us it was cosmetic only but customer perception is more important so we avoid these finishes.

James

James Head BEng CID+ MIIE MIET
Senior PCB CAD Engineer
Crowcon Detection Instruments Limited
2 Blacklands Way
Abingdon Business Park
ABINGDON
OX14 1DY
Telephone: 01235 557700 extension 289
Fax: 07092024504
E-mail: [log in to unmask]


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