APSS-200 Liquid Particle Counter
Do I need cumulative or differential data to determine the number of particle per ml of the product?
Neither differential nor cumulative data will give you particles per mL. You need to divide the volume sampled by the particle data.
Example: If you sample 100 mL of fluid, and your cumulative data shows 1000 particles > 0.1 um, you divide 1000 by 100, and you will have 10 particles (greater than 0.1 um) per mL. You can do the same calculation for differential data.
To learn more about particle counting in liquids read High Resolution Off-Line Liquid Monitoring for Broad Particle Size Distributors.