Maybe this article does not help us, but be sure your answer is in the following:
• ISO 14644-1:2015 focuses on ≥0.1μm, ≥0.2μm, ≥0.3μm, ≥0.5μm, ≥1.0μm and ≥5.0μm particle sizes
• FDA Aseptic guidelines: 0.5μm only
• EU focuses on 0.5 and 5.0μm particle sizes
…Each authority has its own criteria.
Consider that, USP <788>: particulate matter in injections - Particles counting for 10 and 25μm sizes…!
Tnx