"Last Century"?  Thanks for turning me from old to ancient Bev.

As Bev indicated, there are no standards in our industry for this kind of
thing.  The recommended ionic levels from Foresite, PAL, or other test labs
are for circuit assemblies or bare circuit boards, not for amounts in
gloves.  We use standard latex or nitrile gloves here and a lot of what we
use is immersion silver.  We have not seen the need for special gloves.

In terms of functional impact, if it is just tarnish, then there is no
functional impact.  Silver oxide conducts as well as pure silver.  All you
have is a cosmetic issue when people collectively lose their minds looking
at tarnished silver.

I suspect what happened is somebody somewhere thought "sulfur is bad for
silver" (which it is), "so we need sulfur free gloves" (which you don't).

*Douglas Pauls *| Principal Materials and Process Engr | Advanced
Operations Engineering

*COLLINS AEROSPACE*

400 Collins Road NE, MS 108-101, Cedar Rapids, IA  52498  USA

*Tel:* +1 319 295 2109 | *Mobile: *+1 319 431 3773

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On Tue, Jan 14, 2020 at 7:31 AM Bev Christian <[log in to unmask]>
wrote:

> First, do you like to be call GA or Tan?
> a) & b) There are no standards. Shoot, we don't have any "official"
> standards for sodium, potassium, fluoride, chloride, bromide, nitrate,
> nitrate, phosphate or sulfate; unless they are in IEC standards that I
> don't
> know about.  We have the suggestions of Doug and Terry from the last
> century
> and those from Delco and a couple of other sets.
> Certainly the measurement of Doug Pauls, etc. are professionally carried
> out.
> c) Only cosmetic
>
> I have never heard anyone ask for sulfur free gloves. I am not aware of
> what
> is available. I would start with asking a VWR or Fisher rep (large chemical
> suppliers with extensive catalogues) .
>
> Regards,
> Bev
>
>
> -----Original Message-----
> From: TechNet <[log in to unmask]> On Behalf Of Tan Geok Ang
> Sent: January 14, 2020 6:34 AM
> To: [log in to unmask]
> Subject: [TN] Need advice : sulphur level on Gloves/ESD mat and reference
> standards
>
> Will really appreciate advice on the following;
>
> a) how much of sulphur/calcium, etc. on gloves/ESD Mat is acceptable and
> what level is considered harmful in handling of PCBA/module with sliver
> plated surface
>
>
> b) whether there are any "standards" or references for "compliance" check
> for sulphur, and is there such measurements professionally carried out
>
>
> c) What will be the impacts on the PCBA when silver plating become tarnish?
>
>
> There are sulphur free gloves but it is not easily accessible/available in
> Singapore and it is expensive.
>
>
> Thanks.
>
>
> GA Tan
>