Procedure Library
P18.6

Flowability — Angle of Repose and Carr Index

Procedure 16 of 40 · Chapter 18 · §18.1.6

1 table 0 notes

Table 1

Carr Index (%)Hausner RatioFlow CharacterPowder Detergent Implication
0–101.00–1.11ExcellentFree-flowing; ideal for automatic filling and dispensing
11–151.12–1.18GoodSuitable for most packaging operations; minimal flow aid required
16–201.19–1.25FairAcceptable with minor glidant addition; monitor for segregation
21–251.26–1.34PassableRequires flow aid (0.5–2% fumed silica); check bulk handling
26–311.35–1.45PoorSignificant flow aid required; risk of bridging in hoppers
32–371.46–1.59Very poorDifficult to process; reformulation or granulation recommended
>38>1.59Extremely poorNot suitable for commercial powder processing