Benzene / C₆H₆


Gas Identification

Other denomination
CAS Registry Number
SCBA type

Chemical properties

Molecular formula
Molecular mass
78,1 g/mol

Physical properties

Boiling point
80,1 °C
Autoignition temperature
498 °C
Gas/Vapour density
9,24 eV

Flammability limit

1,2 % v/v
8,6 % v/v

Threshold limit value

1 ppm • 3,25 mg/m³
5 ppm • 15,5 mg/m³

Benzene : Description and use


Benzene is an organic compound that can be written as Ph-H, φ-H, or even ϕ-H. It belongs to the monocyclic aromatic hydrocarbon family, as the ring formed by the six carbon atoms is flat and comprises six delocalised electrons.
Under normal conditions, benzene is a colourless liquid with a characteristic odour. It is volatile, highly flammable and carcinogenic.

Flammability: Benzene is a flammable liquid. It easily catches fire in the presence of heat, a source of ignition, an open flame or a spark (including electrostatic discharge). Benzene vapours are heavier than air and can cover a great distance towards a source of ignition causing a flashback. When it flows or is mixed, benzene can accumulate an electrostatic charge, produce a spark and cause a fire. The liquid floating on water could move towards a source of ignition and cause a fire to spread.
Explosiveness: Benzene vapours can form an explosive mixture with air. Benzene can explode upon contact with strong oxidising agents or upon contact with certain incompatible products.


The sale and use of benzene are strictly controlled, it is used as:

  • A intermediate for synthesis in industry, i.e.:
    • mainly ethylbenzene, cumene, cyclohexane
    • also nitrobenzenes, chlorobenzenes, alkylbenzenes, maleic anhydride, which are base products in many manufacturing processes (styrene, phenol, elastomers, resins, colourants, pesticides, pharmaceutical products, detergents, etc.)
  • An extraction agent in the perfume industry but this use has been becoming redundant in France since 1995.
  • In analytical laboratories and in research.
  • Finally, it is naturally present in fuels (particularly in unleaded petrol which can contain up to 1% in volume) and in several petrol-derived products and in complex substances produced from coal.

Benzene : Warnings and caution

GHS hazard statements

H225 - Highly flammable liquid and vapour.
H350 - May cause cancer.
H340 - May cause genetic defects.
H372 - Causes damage to organs through prolonged or repeated exposure.
H304 - May be fatal if swallowed and enters airways.
H319 - Causes serious eye irritation.
H315 - Causes skin irritation.

GHS precautionary statements

P202 - Do not handle until all safety precautions have been read and understood.
P210 - Keep away from heat, hot surfaces, sparks, open flames, any other source of ignition. No smoking.
P280 - Wear protective gloves/eye protection.
P302+P352 - IF ON SKIN: Wash with plenty of soap and water.
P305+P351+P338 - IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
P308+P313 - IF exposed or concerned: Get medical advice/attention.

SGH02 : Inflammable
SGH08 : Sensibilisant, mutagène, cancérogène, reprotoxique
SGH07 : Toxique, irritant, sensibilisant, narcotique