RT Journal Article SR Electronic T1 Understanding the Non-Equivalency of Bio-Fluorescent Particle Counts versus the Colony Forming Unit JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP pdajpst.2022.012790 DO 10.5731/pdajpst.2022.012790 A1 Joanny Salvas A1 Petra Merker A1 Mike Dingle A1 Cedric Joossen A1 Chris Knutsen A1 David Govezensky A1 Jim Cannon A1 Philip Villari A1 Anthony M Cundell A1 Victoria Navarro A1 Margit Franz-Riethdorf A1 Allison Scott YR 2023 UL http://journal.pda.org/content/early/2023/07/14/pdajpst.2022.012790.abstract AB Adopting emerging microbiological methods is often desirable because it enables more advantageous, real time monitoring practices. However, when the newer method measures contamination based on a different detection principle and provides results that are based on different units of measure, a paradigm shift is necessary. That shift can be one of the most difficult challenges in any such project and requires careful consideration. In this paper, we explore the challenges presented by the Bio-Fluorescent Particle Counting (BFPC) technology, when considering that the traditional Colony Forming Unit (CFU) is the gold standard which any change is measured against. We examine why attempts to correlate newer units of measure used by Bio-Fluorescent Particle Counters, namely the Auto-Fluorescent Units (AFUs), to the traditional CFUs are not necessarily appropriate. The paper explores in depth why there is no consistent correlation factor between the two units of measure, and why that should not be a barrier to fully leveraging, implementing, and using such modern technologies in routine monitoring.