To All Technetters,

Being from purchasing, I have been asked to rationalize the inherent cost for
demanding quality standards that my company now prescribes to.

Below, I have outlined our company's test criteria for environmental stress
testing:

Panel Allocation                             Test Description
Thermal Cycle -55C / 150C    X1            15 Min x 2 x 100; Test PC boards
without components
Humidity 85/85                   X2            7 Days; Test complete units

150C Bake                          X3              7 Days
Hot Plate/ Oil Temp Shock    X4            10 Sec x 20  0C-100C Water Dip

Via Current                            X5              7 Days / 14 cycles @
25C & 125C

Below, I have outlined several questions so that I can attain a richer
understanding of the intent, benefit and drawbacks of environmental stress
testing:

a.  How would moisture absorption effect results of environmental stress
testing?
b.  How would soldermask adhesion be effected by environmental stress testing?
c.  How is oxidation formed; is it a function of water
absorption/environmental exposure?
d.  What could cause via current test (the via are burnt and opened) after
environmental stress testing?
e.  If our product is not exposed to any harsh environmental conditions, what
is the benefit for this type of testing?

I would appreciate any and all comments and feedback all of you have to offer.

Regards,