Ammonium nitrate

Flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

flammable solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is known to be stable in contact with air at room temperature for prolonged periods of time (days) and hence, the classification procedure does not need to be applied

Reference 2

Endpoint:

substances / mixtures which in contact with water emit flammable gases

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the experience in production or handling shows that the substance does not react with water, e.g. the substance is manufactured with water or washed with water

Reference 3

Endpoint:

pyrophoric solids

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is known to be stable in contact with air at room temperature for prolonged periods of time (days) and hence, the classification procedure does not need to be applied

Reference 4

Endpoint:

self-heating substances / mixtures

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
Ammonium nitrate is an oxidizing inorganic salt. Heating will result in oxidation of the ammonium ion by the nitrate ion and reduction of the nitrate ion by the ammonium ion; the substance decomposes into N2O and water molecules.
NH4NO3 ---> N2O + 2H2O
This (exothermic) decomposition reaction probably takes place above its melting temperature of 169.6°C.
Ammonium nitrate will not react with oxygen in the air and will therefore not be a self-heating substance.

Supporting information:
-Nitrogen in the nitrate is on the highest oxidation level (+5) .
-Ammonium nitrate is not a flammable solid.

Reference 5

Endpoint:

pyrophoric solids

Type of information:

not specified

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: secondary source

Guideline:

other: not mentioned

Principles of method if other than guideline:

no information in the reference

GLP compliance:

not specified

Key result

Test procedure:

ignition time on contact with air

Remarks on result:

no ignition on contact with air (not further specified)

According to the National Fire Protection Agency (NFPA), ammonium nitrate has a flammability of 0, which includes any material that will not burn.

Interpretation of results:

study cannot be used for classification

Conclusions:

According to the National Fire Protection Agency (NFPA), ammonium nitrate has a flammability of 0, which includes any material that will not burn.

Description of key information

Ammonium nitrate is an oxidizing inorganic salt. Heating will result in oxidation of the ammonium ion by the nitrate ion and reduction of the nitrate ion by the ammonium ion; the substance decomposes into N2O and water molecules.

NH4NO3 ---> N2O + 2H2O

This (exothermic) decomposition reaction probably takes place above its melting temperature of 169.6°C.

Ammonium nitrate will not react with oxygen in the air and will therefore not be a self-heating substance.

Supporting information:

-Nitrogen in the nitrate is on the highest oxidation level (+5) .

-Ammonium nitrate is not a flammable solid.

Key value for chemical safety assessment

Flammability:

non flammable

Justification for classification or non-classification

Based on the available data, no classification for ammonium nitrate according to CLP Regulation (EC) No 1272/2008 for the following hazards:

- Flammable solids

- Pyrophoric solids

- Self-heating substances

- Substances which in contact with water emits flammable gases