Strontium zirconium trioxide

Oxidising properties

Link to relevant study record(s)

Reference

Endpoint:

oxidising solids

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 March 2018 - 16 May 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The oxidising properties of the test material were investigated at the "German Bundesanstalt für Materialforschung und -prüfung (BAM)" in accordance with the standardised guidelines Test O.1 of the United Nations Recommendations on the Transport of Dangerous Goods Manual of Tests and Criteria, 6th revised edition 2015.

Qualifier:

according to guideline

Guideline:

other: Test O.1 of the United Nations Recommendations on the Transport of Dangerous Goods Manual of Tests and Criteria, 6th revised edition 2015.

Deviations:

yes

Remarks:

see below

Qualifier:

according to guideline

Guideline:

other: Section 2.14 of Annex I of Regulation (EC) No 1272/2008 of 16 December 2008 on Classification Labelling and Packaging of Substances and Mixtures.

Deviations:

no

GLP compliance:

no

Remarks:

The test was performed under GLP similar conditions but not under GLP conditions. Therefore this study was considered as reliable for the evaluation of the oxidising properties of this inorganic test substance.

Contact with:

powdered cellulose

Duration of test (contact time):

> 180 s

Key result

Sample tested:

1:1 sample-to-cellulose ratio

Parameter:

mean burning time

Result:

> 180 s

Remarks on result:

other: combustion with orange flame

Key result

Sample tested:

4:1 sample-to-cellulose ratio

Parameter:

mean burning time

Result:

> 180 s

Remarks on result:

other: slow combustion with orange-coloured flame

Key result

Sample tested:

reference: 3:7 mixture potassium bromate + cellulose

Parameter:

mean burning time

Result:

127 s

Remarks on result:

other: Smoking combustion

Table 1 The Results of the Reference Mixture of Potassium Bromate and Cellulose in the Ratio of 3:7 (by Mass)

Test no.	Burning time [s]
1	137
2	109
3	135
4	135
5	127

Mean burning time (s) = 127

Observation: Smoking combustion

 

Table 2 The results of the Test Material and Cellulose Mixture in the Ratio of 4:1 (By Mass)

Test no.	Burning Time (s)	Observations
1	>180
2	179	Wire breakage with immediate reaction stop, in case of incomplete substance conversion.
3	170	Wire breakage with immediate reaction stop, in case of incomplete substance conversion.
4	140	Wire breakage with immediate reaction stop, in case of incomplete substance conversion.
5	-	Substance material depleted. No further measurements possible.

Mean burning time (s) = >180

 

Table 3 The results of the Test Material and Cellulose Mixture in the Ratio of 1:1 (By Mass)

Test Number	Burning Time (s)	Observations
1	>180	Burn-up with orange flame
2	>180	Burn-up with orange flame
3	>180	Burn-up with orange flame
4	>180	Burn-up with orange flame
5	>180	Burn-up with orange flame

Mean burning time (s) = >180

 

Discussion

The ignition wire broke during each of the tests for the mixtures of test material and cellulose in the mixing ratio 4:1. Breaking of the ignition wire often occurs with test material and cellulose mixtures but this is not the case for the reference mixtures. Test O.1 states that if the wire breaks during the test, then the test should be repeated unless the wire breaking clearly does not affect the result. In each case that the wire broke, it was judged not to have affected the test.

As the mean burning times for the mixtures of test material and cellulose were greater than the mean burning time for the 3:7 (by mass) mixture of potassium bromate and cellulose, it was not necessary to determine the mean burning times for the faster burning reference mixtures.

Interpretation of results:

other: no oxidising properties

Conclusions:

Under the conditions of this study, the test material is not an oxidising solid. It requires no classification in accordance with either the UN GHS or CLP regulations. 

Executive summary:

The oxidising properties of the test material were investigated in accordance with the standardised guidelines Test O.1 of the United Nations Recommendations on the Transport of Dangerous Goods Manual of Tests and Criteria, 6th revised edition 2015. The GHS/CLP classification is based on the Globally Harmonised System of Classification and Labelling of Chemicals (GHS), seventh revised edition 2017 and Regulation (EC) No. 1272/2008 (CLP Regulation). It was assigned a reliability score of 1 in accordance with the criteria detailed by Klimisch (1997).

For the tests, the test substance was mixed with dry fibrous cellulose in the mass mixing ratios1: 1 and 4: 1 (test substance to cellulose). The combustion times of these mixtures were compared with reference mixtures, mass mixing ratio 3: 7, 2: 3 and 3: 2 (potassium bromate to cellulose). Cellulose with a fibre length between 50 µm and 250 µm was used as flammable

material.

If the test substance would have contained more than 10 % by mass of particles with a diameter of less than 500 µm, the entire test substance would have to be ground/mortarized into a

powder prior to the test, in order to take into account the abrasion generated during transport/handling.

Since the test substance "strontium zirconate" (223/230318/01) provided by Treibacher Industrie AG did not contain any particles smaller than 500 µm it was tested as delivered.

Results:

The mean combustion times (t1 > 180 s and t2 > 180 s) of the 1 : 1 and 4: 1 mixing ratios of both test substances to cellulose are greater than the mean combustion time of 3 : 7 mixing ratio of potassium bromate to cellulose (R1 = 127 s).

Due to the slow combustin of the mixing ratio test substance to cellulose measurements of the combustion times of the mixing ratios pottasium bromate to cellulose 2:3 (R2) and 3:2 (R3) were not performed.

Under the conditions of this study, the test material is not an oxidising solid. It requires no classification in accordance with either the UN GHS or CLP regulations. 

Description of key information

The test material is not an oxidising solid. 

Key value for chemical safety assessment

Oxidising properties:

no

Additional information

The oxidising properties of the test material were investigated in accordance with the standardised guidelines Test O.1 of the United Nations Recommendations on the Transport of Dangerous Goods Manual of Tests and Criteria, 6th revised edition 2015. The GHS/CLP classification is based on the Globally Harmonised System of Classification and Labelling of Chemicals (GHS), seventh revised edition 2017 and Regulation (EC) No. 1272/2008 (CLP Regulation). It was assigned a reliability score of 1 in accordance with the criteria detailed by Klimisch (1997).

For the tests, the test substance was mixed with dry fibrous cellulose in the mass mixing ratios1: 1 and 4: 1 (test substance to cellulose). The combustion times of these mixtures were compared with reference mixtures, mass mixing ratio 3: 7, 2: 3 and 3: 2 (potassium bromate to cellulose). Cellulose with a fibre length between 50 µm and 250 µm was used as flammable material.

If the test substance would have contained more than 10 % by mass of particles with a diameter of less than 500 µm, the entire test substance would have to be ground/mortarized into a powder prior to the test, in order to take into account the abrasion generated during transport/handling.

Since the test substance "strontium zirconate" (223/230318/01) provided by Treibacher Industrie AG did not contain any particles smaller than 500 µm it was tested as delivered.

Results:

The mean combustion times (t1 > 180 s and t2 > 180 s) of the 1 : 1 and 4: 1 mixing ratios of both test substances to cellulose are greater than the mean combustion time of 3 : 7 mixing ratio of potassium bromate to cellulose (R1 = 127 s).

Due to the slow combustin of the mixing ratio test substance to cellulose measurements of the combustion times of the mixing ratios pottasium bromate to cellulose 2:3 (R2) and 3:2 (R3) were not performed.

Under the conditions of this study, the test material is not an oxidising solid. It requires no classification in accordance with either the UN or CLP regulations. 

Justification for classification or non-classification

Based on the above data, strontium zirconium trioxide does not require a classification regarding its oxidising properties, neither under CLP nor UN GHS.