Bioburden in overkill and particulate in sterile

GOOD VALIDATION PRACTICE (cGVP)
1

Dear All my validation collegue,

I have 2 questions

  1. Is it true that we can skip the Bioburden Challenge test if we apply overkill approach. It seems logic and reasonable.

  2. Why certain liquid for injection (which using 0.22um filtration process) are allowed to have ‘particulate matter’ in their sterile finished product. It doesn’t seems reasonable.

Mokhzanni.