Trisodium bis[4-[4,5-dihydro-4-[(2-hydroxy-5-nitrophenyl)azo]-3-methyl-5-oxo-1H-pyrazol-1-yl]benzene-1-sulphonato(3-)]cobaltate(3-)

Oxidising properties

Link to relevant study record(s)

Reference

Endpoint:

oxidising solids

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From October 18th to 24th, 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

UN Manual of Tests and Criteria: Test O.1 (Test for oxidizing solids)

Version / remarks:

2015

GLP compliance:

yes (incl. QA statement)

Contact with:

powdered cellulose

Duration of test (contact time):

3 min

Sample tested:

1:1 sample-to-cellulose ratio

Parameter:

mean burning time

Result:

> 180 s

Remarks on result:

mixture does not ignite and burn

Sample tested:

4:1 sample-to-cellulose ratio

Parameter:

mean burning time

Result:

> 180 s

Remarks on result:

mixture does not ignite and burn

Residual moisture

The test item contained a residual moisture of < 0.1 wt. %, which was determined by drying at 50 °C under vacuum.

The reference item potassium bromate contained a residual moisture of < 0.1 wt. %, which was determined by drying at 65 °C.

The reference item cellulose contained a residual moisture of 5.94 wt. %, which was determined by drying at 105 °C.

Oxidizing properties

Burning times of the reference mixtures of potassium bromate and cellulose

Potassium bromate – cellulose	test 1 / s	test 2 / s	test 3 / s	test 4 / s	test 5 / s	average / s
3:7	115	128	123	110	115	118
2:3	/	/	/	/	/	/
3:2	/	/	/	/	/	/

The tests with the mixtures potassium bromate:cellulose 2:3 and 3:2 were not performed, because the burning time of the mixtures of the test item with cellulose was higher than the burning time of the reference mixtures 3:7.

Burning times of the mixtures of the test item and cellulose

Test item – cellulose	test 1 / s	test 2 / s	test 3 / s	test 4 / s	test 5 / s	average / s
4:1	> 180	> 180	> 180	> 180	> 180	> 180
1:1	> 180	> 180	> 180	> 180	> 180	> 180

Due to the tests the test item has not to be classified as oxidizing solid.

Interpretation of results:

other: not classified according to the CLP Regulation (EC 1272/2008)

Conclusions:

Due to the test results, test item has not to be considered as an oxidizing solid.

Executive summary:

The burning time of the mixtures of test item Acid Brown 303 with cellulose (4:1 and 1:1) was higher than the burning time of the reference mixture of potassium bromate and cellulose (3:7).

Accordingly, test item does not have to be considered as an oxidizing solid.

Description of key information

Non oxidising.

Key value for chemical safety assessment

Oxidising properties:

non oxidising

Additional information

UN test O.1.

Justification for classification or non-classification

Oxidising solid means a solid substance or mixture which, while in itself is not necessarily combustible, may, generally by yielding oxygen, cause, or contribute to, the combustion of other material.

Classification criteria are reported in the CLP Regulation (EC 1272/2008). An oxidising solid shall be classified in one of the three categories for this class using test O.1 in Part III, sub-section 34.4.1 of the UN Manual of Tests and Criteria in accordance with Table 2.14.1:

- category 1: any substance or mixture which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time less than the mean burning time of a 3:2 mixture, by mass, of potassium bromate and cellulose.

- category 2: any substance or mixture which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time equal to or less than the mean burning time of a 2:3 mixture (by mass) of potassium bromate and cellulose and the criteria for category 1 are not met.

- category 3: any substance or mixture which, in the 4:1 or 1:1 sample-to-cellulose ratio (by mass) tested, exhibits a mean burning time equal to or less than the mean burning time of a 3:7 mixture (by mass) of potassium bromate and cellulose and the criteria for categories 1 and 2 are not met.

As no burning of the test item to cellulose mixture occurs during the test time, i.e. up to 180 s, test item is considered as a non oxidising solid and is not classified within the CLP Regulation (EC 1272/2008).