I believe the J-STD-033 (or perhaps 020) states that the moisture indicator level right at the time of opening is the representative level of the parts for determining if a bake is needed, not the level some time thereafter. In some packaging the MIC status can be seen through the bag, but if not, then the level indicated right at the time of opening is used to assess dryness (or lack thereof). The paper MIC will absorb moisture much faster than a plastic component.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
Sent: Monday, April 23, 2018 10:25 AM
To: [log in to unmask]
Subject: [TN] HIC Card validity?
Morning all,
I have a question regarding HIC cards. We have one style here in our stock room that we have new in a can. Last Thursday when it was 77% relative humidity, you could take one of the HIC cards out of the can (it was the lower right hand card in the photo) and literally watch the 5% & 10% dots turn pink within 20-minutes. So according to the card, if a sealed MBB that contained MSL3 parts was opened, and 20-minutes later both dots turned pink I would have to bake the parts, correct? The problem with that is that the bag was only opened for 20-minutes, not 168-hours. I'm just asking the question the same way a stockroom clerk would ask it. What are they supposed to do when they see a pink card?
http://stevezeva.homestead.com/HIC_Cards.jpg
BTW, all three cards have been sitting out all weekend and came in with bare PCB's and other parts that we received in. I know the humidity has been at least 77% over the weekend, and it's 57% this morning. All the dots on all the cards should be pink, correct? How much faith do you put in the HIC cards when you see this kind of variability?
Steve
--
Steve Gregory
Kimco Design and Manufacturing
Process Engineer
(208) 322-0500 Ext. -3133
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