Chromium hydroxide sulphate

Particle size distribution (Granulometry)

Link to relevant study record(s)

Reference

Endpoint:

particle size distribution (granulometry)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Justification for type of information:

Company data described in detail.
Methods used large sieve size in view of large particles formed during normal production. Lower sieve sizes were not considered necessary to demonstrate low dustiness.

Qualifier:

no guideline followed

Principles of method if other than guideline:

Apparatus
Sieves of 250 and 63 µm

4.2 Analytical balance.



5. Procedure

5.1 Stack the sieves and place on the top sieve a weigh of the substance or material to be
tested.

5.2 Shake the sieves with a left to right motion for 5 minutes.

5.3 Weigh the material retained on each sieve to 2 decimal places



6. Calculation

6.1 The weight retained on each sieve if expressed as a % of the total initial weight of the substance being tested.


7. Report

7.1 Report each fraction retained by each sieve expressed as % of the total +/-
2 x SD.

GLP compliance:

no

Type of method:

sieving

Type of particle tested:

primary particle

Type of distribution:

mass based distribution

Specific details on test material used for the study:

Batch number of test material: A-09-03021

Mass median aerodynamic diameter:

> 250 µm

Key result

Percentile:

D90

Mean:

> 250 µm

Remarks on result:

other: Statistical analysis not applied

Sieve µm	Wt in grams	Mean	SD	2xSD	Variance
250	45.32
	45.89
	46.02
	45.57
	45.68
	45.38
	45.97
	46.05
	45.78
	45.91	45.76	0.26162	0.52324	0.06845
63	2.96
	2.55
	2.97
	2.58
	2.63
	2.57
	2.49
	2.51
	2.53
	2.68	2.65	0.17658	0.35316	0.03118
< 63	0.48
	0.49
	0.38
	0.47
	0.46
	0.41
	0.39
	0.45
	0.47
	0.39	0.41	0.1039	0.2078	0.0108

Conclusions:

The particle size was found to be > 250 micron. An assessment of the dust content was made on the basis of particles passing through a 63 micron sieve. The amount by weight of particles of less than 63 microns was 0.86 %.

Executive summary:

The particle size was found to be > 250 micron. An assessment of the dust content was made on the basis of particles passing through a 63 micron sieve. The amount by weight of particles of less than 63 microns was 0.86 %.

 

Description of key information

The particle size was found to be > 250 micron. An assessment of the dust content was made on the basis of particles passing through a 63 micron sieve. The amount by weight of particles of less than 63 microns was 0.86 %.