hydrogen cyanide; hydrocyanic acid
CAS 74-90-8 · CHN
Hazard classDanger — Toxic, Environmental hazard
PictogramsToxicEnvironmental hazard
H-statements- H330 Fatal if inhaled
- H310 Fatal in contact with skin
- H300 Fatal if swallowed
- H400 Very toxic to aquatic life
- H410 Very toxic to aquatic life with long lasting effects
Common uses (US EPA CDR)Intermediate
Workplace exposure limitsNIOSH REL ST 4.7 ppm (5 mg/m3) [skin]
OSHA PEL TWA 10 ppm (11 mg/m3) [skin]
IDLH 50 ppmOccupational exposure limits — NIOSH Pocket Guide.
Synonymshydrogen cyanide · hydrocyanic acid · Formonitrile · Prussic acid · Blausaeure · Cyanwasserstoff · Formic anammonide · Cyclon
Molecular weight27.025 g/mol
Data sourceHarmonised classification ECHA — EU CLP Annex VILegally binding EU classification adopted by ECHA under CLP Annex VI — the highest-confidence GHS source.
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