Boron carbide

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

flammable solids

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Data from secondary literature.

Qualifier:

according to guideline

Guideline:

other: VDI 2263

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.10 (Flammability (Solids))

Deviations:

no

Principles of method if other than guideline:

The methods of the various determinations are in detail explained in the attached background material:

Determination of the Lower explosion limit LEL
Determination of the combustibility
Determination of the maximum explosion (over)pressure pmax
Determination of the KSt value

GLP compliance:

not specified

Test procedure:

ignition time on contact with air

Remarks:

Ignition on contact with air refers to either Pyrophoric solids or Pyrophoric liquids depending on physical state (migrated information).

Remarks on result:

no ignition on contact with air (not further specified)

Remarks:

corresponding to 'no' in migrated source record.

Test procedure:

ignition time on contact with air

Remarks:

Ignition on contact with air refers to either Pyrophoric solids or Pyrophoric liquids depending on physical state (migrated information).

Remarks on result:

no ignition on contact with air (not further specified)

Remarks:

corresponding to 'no' in migrated source record.

Combustibility

BZ 1 (does not catch fire)

Interpretation of results:

non flammable

Remarks:

Migrated information

Conclusions:

Boron carbide dust in not flammable.

Reference 2

Endpoint:

flammable solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

Boron Carbide („Black Diamond“), a covalent non-metallic carbide, is an inorganic solid with a high chemical inertness. With a hardness of 9.3 on the mohs scale, it is one of the hardest materials known, behind cubic boron nitride and diamond. It does not noticeably react with chlorine or oxygen below 1,000 °C, is completely inert against hydrogen fluoride and hot nitric acid and is practically insoluble in water (see section 4.8 of the IUCLID dossier) and organic solvents [1].

Comparing the physico-chemical properties and structural elements of boron carbide with the physic-chemical properties and structural parts of substances known to be flammable, indicates that boron carbide is highly unlikely to show these foreseen properties.

Long-term experience in manufacturing, handling and use of boron carbide supports the assumption of boron carbide being not flammable. Preliminary results with boron carbide powder of particle size 1200mesh according to VDI 2263 show that boron carbide is not flammable using an ignition source of 1,000°C.

Due to the inherent properties of boron carbide (no relevant functional groups known to contribute to flammability, very inert material, no noticeably reaction with chlorine or oxygen below 1,000 °C), performance of a study to determine the flammability of boron carbide is considered not to be necessary.

Key value for chemical safety assessment

Flammability:

not classified