You need triple layer bags: PE outside, then Al, then PP inside. Brian Nancy Reynolds/MKT/HQ/KEMET/US wrote: > > Hi TechNetters, > > Archives show that this question has been asked several times over the last > year, but I find no answers... > > IPC/JEDEC J-STD-033, dated May 1999, states the WVTR for MBBs must be > <=0.002 g/100 sq inch in 24 hours at 40C. I can find bags that meet <= 0.02 > g/100 sq inch, but nowhere have I found a bag at 0.002. Is this a typo in > J-STD-033? And if not, can anybody tell me where to look for bags that > meet this requirement? Should I assume the formula for calculating how > many desiccant units are required is correct as stated? Sure is a lot of > desiccant if the actual WVTR is 0.02 g/100 sq inch. > > TIA > Nancy > > Nancy Reynolds > Product Manager > KEMET Electronics= > > --------------------------------------------------------------------------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > 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 delivery of Technet send the following message: SET Technet NOMAIL > Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives > Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional > information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 > --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------