Thanks everyone for the information on critical limits for physical risks, especially the FDA link.
I work at a flour mill and our CCP is a turbosifter that has 5 mm openings, which means that everything larger than 5 mm is rejected. Because of the equipment´s capacity, this also means that a lot of flour is also sent to the rejection bin. This is later reprocessed. Because a large part of the milling process is sifting (our specification says that 100% of flour goes through a sieve that has 180 microns), any physical risks would be eliminated along the way.
We´d been considering reducing the openings on our turbosifter to 2.0 mm simply because our sister mills all have them that way. However thanks to the info on this forum we´ll keep it as it is.
Just one question: most decision trees for the determination of PCCs say that if the step is set up specifically to reduce / eliminate the risk of a hazard, it is a PCC. In that case, our separator (it eliminates any particles that do not have the size, shape and density of wheat) would be a PCC. However, there are other steps further down the line that eliminate physical hazards.
The decision tree is applied in reference to a a particular hazard. If a particular hazard is not taken care at turbosifter and at other processing step down the flow chart then for that hazard that step down the flow chart becomes the CCP.
If all the physical hazards are taken care at the tubosifter itself then no need to have additional steps to to control physical hazards and turbo sifter becomes the CCP.
There might be another scenerio: -
The hazards are introduced after the turbosifter step. In that case you need to have those additional steps to control physical hazards and they become the ccp/cp dependig upon other considerations.
Requesting the opinion from the forum.