BS 3406-5:1983

Foreword
Cooperating organizations
Recommendations
0. Introduction
1. Scope
2. Definitions
3. Symbols and abbreviations
4. Health and safety
5. Principle
5.1 General operation
5.2 Response theory
5.3 Effect of particle shape and orientation
5.4 Effect of coincident particle passage
5.5 Pulse shape
5.6 Size limits
6. Operational procedures
6.1 Instrument location
6.2 Choice of electrolyte solution
6.3 Electrolyte solution preparation
6.4 Sample preparation and dispersion
6.5 Choice of orifice(s) and monometer setting(s)
6.6 Stability of dispersion
6.7 Clearing an orifice blockage
6.8 Analytical procedure
6.9 Background counts
6.10 Calibration
6.11 Multiple orifice method for wide size range samples
6.12 Calculation of results
6.13 Extrapolation
6.14 Determination of mass percentage detected
7. Reporting of results
Appendices
A. Comparison with other methods
B. List of suitable elecrolyte solutions
C. Instrument checks
D. Measurement of the immersed density of particles
    of powder when dispersed in electrolyte solution
E. Example of calibration by mass integration
F. Example of determination of percentage mass
    analysed
G. Large orifice technique (orifice diameter >560 mu m)
H. Bibliography
Tables
1. Background counts
2. Suggested manometer settings
3. Stability of suspension
4. Typical coincidence correction chart
5. Recommended number of counts
6. Suitable orifice diameter combinations
7. Data sheet: normal calculation
8. Data sheet: worked example without corrections
9. Data sheet: large orifice analysis
10. Data sheet: small orifice analysis
11. Worked example (for a 2-orifice analysis)
12. Recommended electrolyte solutions
13. Density of pure water, pw
14. Data for calibration by mass integration
Figures
1. Schematic drawing of a simple form of analyser
2. Pulses
3. Current density at orifice
4. Pulses resulting from axial and non-axial passage
     of particles
5. 2-orifice overlap
6. Example of constant vacuum supply

Gives recommendations on a specific method, the electrical sensing zone method, for the determination of the particle size of powders, and facilitates comparison between size analyses made in different laboratories.