Here's what the 10th edition (1983) of the Merck Index had 
to say on Hydrogen Cyanide.  Notice that there is no 
mention of the gas being explosive:

     HYDROGEN CYANIDE: Hydrocyanic acid, Blauseare, prussic acid. 
     [preparation info deleted] Colorless gas or liquid; 
     characteristic odor; very weakly acidic; burns in air with a 
     blue flame.  INTENSELY POISONOUS EVEN MIXED WITH AIR.  
        Gas density:  0.941 (air = 1)
        Liquid density: 0.687 [g/cm^3, I assume]
        melting point: -13.4 deg Celsius
        Boiling Point: 25.6 deg Celsius
        
      The LC50 (lethal dose for 50% of animals) in rats -- 544 
     ppm (5min), mice 169 ppm (30 min), dogs 300 ppm (3 min).   
     HUMAN TOXICITY:  [..] exposure to 150 ppm for 1/2 to 1 hour 
     may endanger life.  Death may result from a few min. exposure 
     to 300 ppm.  Average fatal dose: 50 to 60 milligrams. 
      USE:  The compressed gas is used for exterminating rodents 
     and insects in ships and for killing insects on trees, etc.  
     MUST BE HANDLED BY SPECIALLY TRAINED EXPERTS.

Home ·  Funding ·  Site Map ·  What's New? ·  Search Nizkor