Hydrogen cyanide - HCN
This page presents information on hydrogen cyanide – or hydrocyanic acid: characteristics, effects on health, detection devices & systems - hydrogen cyanide detector - and respiratory protective equipment (gas mask or PAPR with B gas filter).
Hydrogen cyanide (HCN) properties
Hydrogen cyanide (HCN) - also called hydrocyanic acid or formonitrile – is a chemical compound that can be found in either liquid or gaseous form. Widely used as an insecticide, it is also applied for fumigation applications in the chemical industry. It can be accidentally produced during chemical reactions between cyanide and an acid, or through fire and nitriles combustion.
| CAS | TWA (8 hours) | STEL (15 minutes) | LEL | IP | Density / Air | Filter / Air |
|---|---|---|---|---|---|---|
| 74-90-8 | 0,9 ppm | 4,5 ppm | 5.6 % | 13.6 eV | 0.94 | B |
Hydrogen cyanide effects on health
With variant color from colorless to pale blue, hydrogen cyanide (HCN) is easily detectable through its bitter almond smell. This highly toxic gas (T+) features many harmful or lethal properties. With explosive limits between 5.6 and 40%, this chemical compound is extremely flammable (F+).
Hydrogen cyanide effects on health
Hydrogen cyanide detector (HCN)
Hydrogen cyanide respiratory protection (HCN)
As HCN is highly toxic, it is recommended to use a purifying respiratory protection like a half- mask or a full-face mask for short interventions. A more comfortable powered air purifying respirator equipped with a B filter can also be used for longer time periods. If the HCN concentrations exceed 60 times the OEL, a self-contained breathing apparatus (SCBA) is required to preserve safety.