Pycnometer measures true density (solid only, no voids). Bulk density tester includes voids. For the same powder, bulk density ≤ true density.
USP <616> specifies: 500 taps initially. If volume reduction >2% from 500 to 1250 taps, continue to 2000 taps. Most free-flowing powders stabilize by 500 taps. bulk density tester
This document provides general guidance. Always refer to your specific instrument manual and required regulatory standard for exact test parameters. Pycnometer measures true density (solid only, no voids)
Yes – use a 10 mL or 25 mL cylinder with 0.001 g balance. Some micro-tap density testers exist (e.g., Quantachrome Autotap with 5 mL insert). Pycnometer measures true density (solid only