Ammonia / NH₃


Gas Identification

Other denomination
CAS Registry Number
SCBA type

Chemical properties

Molecular formula
Molecular mass
17 g/mol

Physical properties

Boiling point
-33,35 °C
Autoignition temperature
651 °C
Gas/Vapour density
10,18 eV

Flammability limit

15 % v/v
28 % v/v

Threshold limit value

10 ppm • 7 mg/m³
20 ppm • 14 mg/m³

Ammonia : Description and use


Ammonia is a chemical compound with the formula NH₃ (from the generic group of hydrogen nitrides). It is a colourless gas with a pungent and irritating odour and is lighter than air. It liquefies readily. Very soluble in water (33.1% by weight at 20°C), heat is released when it is dissolved. The solutions obtained are known as ammonia solutions.

Flammability: The risk of ammonia causing a fire is relatively low. It has a flammability limit and can even explode, but it does not catch fire easily. It has to be in contact with materials or a surface with a temperature of 651°C before it will catch fire itself. However, the presence of oil or other combustible materials can increase the risk of fire by reducing this auto-ignition temperature. Ammonia can catch fire upon contact with strong oxidising agents.
Explosiveness: Ammonia requires a concentration of at least 15% (150,000 ppm: fatal concentration) and the presence of a source of ignition to explode. Ammonia can explode upon contact with strong oxidising agents.

  • Refrigeration industry (as a refrigerant)
  • To manufacture electronic or photovoltaic components
  • To manufacture fertiliser
  • Petrol and fuels
  • To treat metals
  • Organic synthesis
  • Textile fibre industry
  • Cleaning solutions
  • Paper industry

Ammonia : Warnings and caution

GHS hazard statements

H221 - Flammable gas.
H280 - Contains gas under pressure; may explode if heated.
H314 - Causes severe skin burns and eye damage.
H331 - Toxic if inhaled.
H400 - Very toxic to aquatic life.

GHS precautionary statements

P260 - Do not breathe gas/mist/vapours/spray.
P271 - Use only outdoors or in a well-ventilated area.
P280 - Wear protective gloves/protective clothing/eye protection/face protection.
P304+P340 - IF INHALED: Remove victim to fresh air and keep at rest in a position comfortable for breathing.
P342+P311 - If experiencing respiratory symptoms: Call a POISON CENTRE or doctor/physician.

SGH04 : Gaz sous pression
SGH06 : Toxique
SGH05 : Corrosif
SGH09 : Danger pour le milieu aquatique