Trisodium bis[3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-4-hydroxy-5-nitrobenzenesulphonato(3-)]chromate(3-)

Auto flammability

Link to relevant study record(s)

Reference

Endpoint:

relative self-ignition temperature (solids)

Type of information:

other: Expert Judgement

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Data derived form expert Judgement

Principles of method if other than guideline:

Expert judgement

GLP compliance:

no

Remarks on result:

other: Expert Judgement

Expert Judgement

Conclusions:

Not autoflammable

Executive summary:

Not autoflammable

Description of key information

non autoflammable

Additional information

The substance is produced and regularly used for many years in Europe, transported in various conditions and in various amounts. Evidence connected to the long experience in handling, use and transport of the substance confirms the non- self-ignition properties. Thus, the substance is expected to be an air-stable compound at room temperature over a prolonged period of time (days), without noticeable or undesirable reactions. In conclusion, a potential for spontaneous ignition is not expected: the substance can be considered as a no-pyrophoric and no-self-heating solid because it is not liable to self-heat by reaction with air and without energy supply. In addition, the substance is very soluble in water at room temperature and forms a stable solution with water. No reactions with water or emission of flammable gases have ever been noted. Furthermore, for soluble dyes a reaction with water is not a desirable property from the use point of view. Therefore, the substance cannot be classified as a substance that in contact with water may react generating flammable gases.

 

Moreover, an existing study on a similar substance was considered as supporting information:

The determination of the auto-ignition temperature of the test item was performed in accordance with the EEC Directive Annex V of 67/548 Test A 15 Auto-ignition temperature for liquids. The auto-ignition temperature of the test item is: no auto ignition up to 550 °C

 

Both AR357 and AR315 are chromate pyrazol sodium salts: AR357 is a trisodium, while AR315 is a disodium salt. They share the same structure, except for the fact that AR357 has two sulphonated groups, instead one as AR315. It is expected that this difference has not impact on the autoignition properties.