VAPOR DENSITY (AIR = 1.0) – 0.932 @ 20° C. (68° F.)
FLASH POINT – 0° C. (32° F.) – Ignites 50% of the time when used in bursting artillery shells
FREEZING/MELTING POINT – -13.3° C. (8° F.)
BOILING POINT – 25.7° C. (78° F.)
DECOMPOSITION TEMPERATURE – >65.5° C. (>150° F.)
LIQUID DENSITY – 0.687 g/cc @ 20° C. (68° F.)
VAPOR PRESSURE (mm/Hg) – 742 mm/Hg @ 25° C. (77° F.), 612 mm/Hg @20° C. (68° F.)
VOLATILITY (mg/m3) – 1,080,000 mg/m3 @ 25° C. (77° F.)
ODOR – Bitter almonds – Detectable by about 60 to 70% of the population at concentrations of 1 to 5 ppm, 20% of the population cannot detect the smell
APPEARANCE – Colorless or light blue liquid
SOLUBILITY – Soluble in water up to 96%
MEDIAN INCAPACITATING DOSAGE (ID50) – Varies widely with concentration
MEDIAN LETHAL DOSAGE (LD50) – Varies widely with concentration
PERSISTENCY – Short, highly volatile agent disperses rapidly in open air
INHALATION TOXICITY – 300 mg/m3 will kill a human being in 10 minutes or less
SKIN TOXICITY – Moderate
EYE TOXICITY – Moderate
RATE OF ACTION – Very rapid, death occurs within 15 minutes when a lethal concentration is encountered
SYMPTOMS (PHYSIOLOGICAL ACTION) – Hyperventilation, giddiness, confusion, loss of consciousness at high concentrations, interferes with use of oxygen by the body
TREATMENT – Immediately remove from exposure, prompt application of oxygen, application of Sodium thiosulfate or Sodium nitrite.
DURATION OF EFFECTIVENESS – Unstable, degrades in atmosphere
PROTECTION – Gas mask, impermeable clothing
DECONTAMINATION – None needed in the field
USE – Frangible hand grenades, artillery and mortar projectiles (limited)
Used by the French as a chemical weapon in 1916, Hydrogen Cyanide was not found to be an effective weapon in the field. Though toxic, the gas was lighter than air and would rapidly disperse into the atmosphere. Both the United States and Italy also used Hydrogen Cyanide as a chemical weapon in 1918, but also found it to be impractical as a battlefield weapon. For World War II, this situation changed. Japan issued globular glass grenades filled with Hydrocyanic acid as a possible antitank weapon. It has been reported that these grenades may have been used against British armored vehicles in Burma. This would be an effective use of the chemical agent as it would seep into openings in the vehicle, lethally poisoning the interior. The United States also considered, and manufactured, frangible toxic gas grenades during World War II. Glass pint bottles were filled with AC agent, the US code name for Hydrogen Cyanide, with the intent that they be used against Japanese caves and underground strongpoints in the Pacific area. These frangible grenades were never issued and stocks of the weapon were destroyed in 1944.
