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Gases - Dangerous Concentration Levels

Dangerous vs. tolerable concentration levels for some industrial gases.

Gases - Dangerous Concentration Levels
GasGas Concentration (0/00)
Tolerable > 1 hourTolerable < 1 hourImmediately Dangerous
Ammonia 0.1 0.3 3.5
Bromine Vapor 0.001 0.004 0.05
Carbon Dioxide 10 30 40
Carbon Monoxide 0.2 0.5 2.0
Chlorine Vapor 0.001 0.004 0.05
Hydrochloric Acid 0.01 0.05 1.5
Hydrogen Sulphide 0.2 0.6
Iodine Vapor 0.0005 0.003 0.05
Sulphuric Acid 0.05 0.5
  • 1 ppm = 10-6 = 0.0001 o/o = 0.001 o/oo
  • o/oo  = 1000 ppm 

Related Topics

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    Human physiology vs. air quality, comfort temperatures, activity and metabolic rates. Health effects of gases adn polutions like carbon monoxide and more.
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