Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

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Substance profile

Phosphine

Phosphine is a colorless gas; flammable with a disagreeable, garlic-like odor.

CAS 7803-51-2 Danger

01 · Identification

What Phosphine is

Phosphine is a colorless gas; flammable with a disagreeable, garlic-like odor. It boils at -87.7 °C, melts at -134 °C, is slightly soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number7803-51-2
EC number232-260-8
Index number015-181-00-1
Chemical class Hazardous Air Pollutants (HAPs)

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Phosphine
CodeHazard statement
H220 Extremely flammable gas.
H330 Fatal if inhaled.
H314 Causes severe skin burns and eye damage.
H400 Very toxic to aquatic life.

Precautionary statements: P210, P233, P260, P271, P273, P280, P301, P304, P310, P331, P391, P403, P501

03 · Physical and chemical properties

Phosphine properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point -87.75 °C (-125.9 °F) HSDB
-87.78 °C (-126 °F) NIOSH
-87.78 °C (-126 °F) at 760 mmHg CAMEO
Melting point -133.8 °C (-208.8 °F) HSDB
-133.89 °C (-209 °F) NIOSH
-132.78 °C (-207 °F) CAMEO
Density 0.0015 g/cm³ ICSC
0.8 g/cm³ ICSC
0.0014 g/cm³ at 25 °C HSDB
Solubility Insoluble in water HSDB
Slightly soluble in cold water. Insoluble in hot water. HSDB
Slightly soluble in water (0.26 volume at 20 °C) at 20 °C HSDB
Vapor pressure 31390 mmHg NIOSH
26160 mmHg at 20 °C ICSC
29300 mmHg at 25 °C HSDB
Flash point NA (Gas) NIOSH
Flammable gas ICSC
Autoignition temperature 100 °C (212 °F) HSDB
38 °C (100.4 °F) ICSC
Lower explosive limit (LEL) 1.79 % by volume NIOSH
1.6 % by volume estimated ICSC
Upper explosive limit (UEL) 100 % by volume estimated ICSC
Dangerous fire hazard from spontaneous chemical reaction. (EPA, 1998) CAMEO
Dangerous fire hazard from spontaneous chemical reaction. OSHA
Vapor density 1.17 (air = 1) HSDB
1.18 (air = 1) ICSC
Odor threshold 0.03 PPM HSDB
Air: 0.51 uL/L; Water: 0.0002 mg/L; Odor Safety Class: D; D= 10-50% of attentive persons can detect TLV concn in the air. HSDB
Phosphine's characteristic decayed fish odor is barely detectable at concentrations of 1.5 to 3 ppm. HSDB
Critical temperature and pressure 51.35 °C (124.4 °F) HSDB

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Phosphine

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Contents under pressure. Storage class (TRGS 510): Gases.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Strong oxidizing agents, oxidizing agents, halogens, nitric acid.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

PHOSPHINE is a reducing agent. Ignites spontaneously in air when pure [Sidgwick, 1950, p. 729]. Liquefied phosphine can be detonated [Rust, 1948, p. 301]. Ignites or reacts violently with boron trichloride, dichlorine oxide, halogens (bromine, chlorine, iodine), metal nitrates, nitrogen oxides, nitric acid, nitrous acid, nitrogen trichloride [Bretherick, 5th ed., 1995, p. 1562]. Forms explosive mixtures with even small amounts of oxygen. Autoignites at low pressures [Fisher, E. O. et al., Angew. Chem., 1968, 7, p. 136].

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Phosphine in the storage compatibility matrix →

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