3,5-dimethylpyrazole

Flammability

Link to relevant study record(s)

Reference

Endpoint:

flammable solids

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04 May to 17 August 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, with experiments conducted according to appropriate and valid guidelines and conducted under GLP conditions.

Qualifier:

according to guideline

Guideline:

EU Method A.10 (Flammability (Solids))

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: UN N.1: “Test Method for Readily Combustible Solids” 2003.

Deviations:

no

GLP compliance:

yes

Key result

Test procedure:

burning time (test type not further specified)

Remarks:

or specified in description of method (migrated information)

Burning time:

>= 55 - <= 92 s

Preliminary Test

The flame of a gas burner did ignite the pile. The test material melted and burned with a yellow/blue flame and turned into a brown/black residue. Grey/black smoke was observed. The burning time over a distance of 200 mm, after the pile had burned a distance of 50 mm, was 206 seconds. Based on this result the burning rate test was selected as the appropriate method for the main test.

 

Main Test

The burning times over 100 mm, after the pile had burned a distance of 80 mm, are shown in Table 1.

All burning times exceeded 45 seconds. According to this, the test material is considered ‘not highly flammable’.

In all 6 tests propagation of combustion was not stopped by the wetted zone.

Table 1. Burning Times

Test No.	Burning Time Over 100 mm (s)*
1	86
2	86
3	55
4	63
5	92
6	90

*Time measured after the pile had burned over 80 mm.

Interpretation of results:

non flammable

Remarks:

Migrated information

Conclusions:

Under the conditions of the test, the test material is considered to be ‘not highly flammable’. The test material burned with a yellow/blue flame with a burn time of between 55 and 92 seconds, combustion was not stopped by the wetted zone. As the burn time was not less than 45 seconds, the test material is not classified as flammable.

Executive summary:

The flammability of the test material was determined using the burning rate test in a study performed in accordance with GLP and to the standardised guidelines EU method A. 10 and UN N.1.

A preliminary study was performed to establish the appropriate test method for the main study. As the test material propagated burning over a 200 mm length in less than 4 minutes the burning rate test was performed.

Under the conditions of the test, the test material is considered to be ‘not highly flammable’. The test material burned with a yellow/blue flame with a burn time of between 55 and 92 seconds, combustion was not stopped by the wetted zone. As the burn time was not less than 45 seconds, the test material is not classified as flammable.

Description of key information

The flammability of 3,5-Dimethylpyrazole was determined by performing the burn test (Baltussen, 2012) according to GLP and the standardised guidelines EU method A. 10 and UN Test N.1.

Pyrophoric Properties of Solids and flammability in contact with water, have both been waived based on the chemical structure of the test material.

Key value for chemical safety assessment

Flammability:

non flammable

Additional information

The flammability of the test material has been addressed by providing a key study (Baltussen, 2012) which was performed in accordance with GLP and standardised guidelines. The study was thus assigned a reliability score of 1, in accordance with the principles for assessing data quality as set out in Klimisch (1997).

Testing to assess water reactivity and pyrophoric properties of the test material have been omitted in accordance with Section 1.5 of REACH Annex XI, which states that these studies need not be performed if flammability is not expected based on the chemical structure of the test material.

Justification for classification or non-classification

In accordance with Regulation EC No. 1272/2008, the test material does not require classification for flammability. The test material is not classified under solid flammability testing as the burn time was determined to be greater than 45 seconds in all performed replicates. Additionally negative results can be predicted for pyrophoric properties and flammability in contact with water, based on the test materials chemical structure. Thus the test material is considered to be non flammable accordingly.