In the fuels world you would have coated the board in polyurethane varnish or such like material

Are you sure that the boards is in direct contact with the gas?
Is it for the oil and gas industry? As if so you might go with a moisture resilient coating. It the moisture that forms the sulphites. I have some information on these materials and their usages

Regards
Paul

Paul Taylor
Alstom Grid | R&D | Post Design Service Team Leader
Phone: +44 (0) 1785 223251 (x2014) | Mobile: +44 (0) 7827 312568 | E-mail: [log in to unmask]
Office address: St Leonards Avenue, Stafford, ST17 4LX
Site: www.alstom.com
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-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Paul Jackson
Sent: 30 July 2014 17:48
To: [log in to unmask]
Subject: [TN] Conformal coating for Sulfur environments

We have a customer whose PCBAs are subjected to flower of sulfur rich environments. The sulfur quickly corrodes any area not covered in soldermask. They would like to use a conformal coating but their research to-date has only come up with one solution which has published data specifically concerning sulfur and the coating is too viscous for their application.

Does anyone have experience with a conformal coating which is proven to survive in an environment with sulfur?

Any help would be greatly appreciated.

Thanks,

Paul
Omni Circuit Boards

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