We currently have all workers working with flour dust (dispensary, mixers etc in FFP3 masks 24/7 the air test shows 1 mg or >1mg in all areas we are considering removing masks as the LEV is proving to work and only using them on high risk areas such as cleaning initially my view was NO but looking at it, the requirement is to use RPE if other measures are not effective and ours are obviously there is a financial gain to this which is a consideration we would be looking at some behaviour training to ensure that procedures are followed (tipping of bags and disposal etc what do you think?

Would FFP2 not be sufficient? The approach you explain seems sensible, however, if P2 is good enough, then you could make the wearing of it mandatory for specific tasks, as you mention, and then still have the masks available for other people on request. You would probably still have some savings as the prices between p3 and p2 vary considerably.