Dear Agnes,
Technically, I would think the US-7mm bogy (hard, sharp objects) is only strictly relevant if you are faced with an American legislative
CCP restriction. If otherwise, it becomes a matter of opinion (IMHO), eg what other limiting opinions exist
for yr product type/end-user application (if any

). (in fact, even tighter restrictions might be possible if vulnerable end-users are involved)
(for general situation, try this review -
foreign material contamination.pdf 286.24KB
121 downloads )
As a corollary to GMO's post and if you are concerned about 7mm limit, one possible option may be to downgrade the hazard risk status. For example if yr data shows that the likelihood of any material >7mm passing through the screen is genuinely "negligible" the "probability of something "large" reaching the finished product" is presumably very low. For most
HACCP plans, L x H (or VLxH) is not a significant hazard. Additionally i believe you can also find some published examples where the severity will only be typically rated as "M" (CFIA from memory for one) which makes a downgrade even easier

.You could then justify making it a prerequisite if you wish to retain the specific "activity" within the
haccp plan.
I also suspect that you can find various, quotable, published
haccp plans which simply regard screening like this as a typical prerequisite anyway, without worrying about the US-7mm worries. A similar approach can be found in the literature in many
haccp plans for the handling of "allergens", a recognised hazard, it often depends on how you conceptually design yr
haccp plan for some tricky situations. Plus it may depend on the auditorial reactions to having a possible NC snatched away.
Rgds / Charles.C