Provenance

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

Build a label

Substance profile

Formaldehyde

Formaldehyde is a nearly colorless gas with a pungent, suffocating odor.

CAS 50-00-0 CH2O 30.026 g/mol Danger

Formaldehyde Safety Data Sheet →

01 · Identification

What Formaldehyde is

Formaldehyde is a nearly colorless gas with a pungent, suffocating odor. Its molecular formula is CH2O and its molecular weight is 30.026 g/mol. It boils at -19.5 °C, melts at -92 °C.

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

CAS number50-00-0
EC number200-001-8
Index number605-001-00-5
Molecular formulaCH2O
Molecular weight30.026 g/mol
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Formaldehyde

  • formalin
  • methanal
  • HCHO
  • Bfv
  • F-Gen
  • Fannoform
  • Floguard 1015
  • Fm 282
  • Formalith
  • Formic Aldehyde
  • Formol
  • Fyde
  • Lysoform
  • Methaldehyde
  • Methyl Aldehyde
  • formaldehyde …%

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 Formaldehyde
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H330 Fatal if inhaled.
H302 Harmful if swallowed.
H314 Causes severe skin burns and eye damage.
H317 May cause an allergic skin reaction.

Supplemental EU statements: EUH071

Precautionary statements: P201, P260, P261, P270, P271, P272, P280, P301, P304, P308, P310, P312, P313, P330, P331, P333

03 · Physical and chemical properties

Formaldehyde 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 -19.5 °C (-3.1 °F) HSDB
19.1 °C (66.4 °F) Formaldehyde 37% uninhibited HSDB
-21.11 °C (-6 °F) NIOSH
Melting point -92 °C (-133.6 °F) HSDB
-92.22 °C (-134 °F) NIOSH
Density 0.8 g/cm³ ICSC
1.08 g/cm³ at 25 °C CAMEO
Solubility In water, 4.00X10+5 mg/L at 20 °C at 20 °C HSDB
In water, 95 weight % at 20 °C at 20 °C HSDB
In water, miscible at 25 °C at 25 °C HSDB
Vapor pressure 1 mmHg Formalin HSDB
1 mmHg CAMEO
3890 mmHg at 25 °C HSDB
Flash point 85 °C (185 °F) Gas HSDB
50 °C (122 °F) Formaldehyde 37%, 15% methanol HSDB
85 °C (185 °F) HSDB
Autoignition temperature 423.89 °C (795 °F) HSDB
430 °C (806 °F) CAMEO
Lower explosive limit (LEL) 7 % by volume HSDB
Upper explosive limit (UEL) 73 % by volume HSDB
Vapor density 1.067 (air = 1) HSDB
1.04 (air = 1) CAMEO
1.08 (air = 1) ICSC
Odor threshold 0.5 to 1.0 ppm HSDB
Detection: media= water: 4.99x10+1 ppm Chemically pure HSDB
Detection: media= water: 2.50x10+1 ppm Purity not specified HSDB
Critical temperature and pressure 139.2 °C (282.6 °F) range, midpoint shown HSDB
Corrosivity Aqueous formaldehyde is corrosive to carbon steel, but formaldehyde in gas phase is not. HSDB

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

04 · Handling and storage

Storing and handling Formaldehyde

Storage conditions

... Minimum storage temperature to prevent polymerization range from 83 °F for 37% formaldehyde containing 0.05% methyl alcohol to 29 °F for formaldehyde containing 15% methyl alcohol.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

(Amines) exothermic reaction, (AZO cmpd) exothermic reaction giving off nitrogen gas, (caustics) heat generation and violent polymerization, (dithiocarbamates) formation of flammable gasses and toxic fumes, formation of carbon disulfide may result, (alkali and alkaline earth metals) heat generation and formation of flammable hydrogen gas, (nitrides) heat generation, formation of flammable ammonia gas and violent polymerization, (nitro compd) heat generation, (unsaturated aliphatics and sulfides) heat generation, (organic peroxides) violent reaction, (oxidizing agents) heat generation, fire, and decomposition, (reducing agents) heat generation and formation of flammable gasses. /From table/

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

FORMALDEHYDE, SOLUTION, reacts violently with strong oxidizing agents (hydrogen peroxide, performic acid, perchloric acid in the presence of aniline, potassium permanganate, nitromethane). Reacts with bases (sodium hydroxide, potassium hydroxide, ammonia), and with nitrogen dioxide (explosive reaction around 180 °C). Reacts with hydrochloric acid to form highly toxic bis(chloromethyl) ether. Polymerization reaction with phenol may develop sudden destructive pressure [Bretherick, 5th ed., 1995, p.168].

Source: CAMEO Chemicals

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

Get the free GHS / CLP / OSHA deadline calendar

Verified 2026–2029 compliance dates in one PDF — plus alerts when the rules change.