Fellow technetters, some questions.

I know that it is sometimes necessary to pre-bake pwb's when there is a
chance that moisture could damage the board when it goes into reflow, or
when it is subject to hot-gas rework. I understand most OEM's and CEM's
do not bake as a matter of standard procedure simply because they
usually do not need to, and baking will diminish solderability. Nearly
all of the delamination issues I have ever seen were invariably caused
by some type of prepreg lamination deficiency. Most of the time nearly
any standard .062" multilayer FR-4 pwb can be reflowed without pre-bake
without danger of delamination, at standard 63/37-based reflow
temperatures. Typically the boards are still dry, and even if they are
not, the prepreg holds up during reflow and rework.

Are there standards for pwb handling that spell out what type(s) of
prepreg materials should be used for different types of pwb's , what the
proper storage methods are, when pre-baking should be performed, at what
temperature and time, etc? Is there a standard that tells us that
certain board types or configurations should be baked (or which ones do
not need to be)? Is there anything out there that provides proper
storage methods for pwb's?

If no standard exists, should not there be one? 

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