Agree.  in addition, the size of the solder ball matters little if you do
not know the pitch of your BGA, fine pitch is not going to be tolerated
0.13 mm size of loose solder ball as clearance is very tight... As Julie
said, process improvement is needed.  if select proper paste and MFG
condition, even 80 micron PITCH (not space) can be achieved...
http://www.mmc.co.jp/adv/ele/en/products/assembly/past-special03.html
Happy Holiday every body.  hopefully, your Pre of Elect bring back some
much needed jobs in electronic industry like Andy Groove once wanted so
badly...(rather than 140 line of characters).
https://www.bloomberg.com/news/articles/2010-07-01/andy-grove-how-america-can-create-jobs

> This is one of the few IPC 610 criteria where Keysight Technologies has an
> objection and includes alternate criteria in our supplemental
> specification.  Likely this objection is also still present in the Agilent
> standards.  (Maybe even HP?  Our leveraging covers several company
> transformations.)  Functionally, the IPC criteria doesn't protect from
> shorting risks.  One objection is to the definition of entrapped.  Over
> time (and our products are in the field for a long time), the balls could
> become dislodged.  Our criteria ignores whether a solder ball is entrapped
> and has size, quantity and reduction in conductor distance requirements.
>
> Your basic problem is that you have work to do on solder paste selection
> and process optimization.  You shouldn't have that sort of spattering.
>