Flammability of hydrogen

A posthumous edition of Turquet de Mayerne mentions the flammability of hydrogen. 

Caution. Due to the high toxicity of carbon monoxide and the high flammability of hydrogen, the reactions must be carried out in a well-ventilated hood. 

Burgoyne and Thomas (17G) have passed mixture air through an iron-electrode arc prior to passing into a Bunsen tube. The effect of the minute iron oxide particles contained in the stream is to lower the lean limit of flammability of hydrogen. Sanger (33G) deals with such topics as the dependency of combustion on pressure, temperature, and the moisture content of powders, and gives a series of equations in support of his hypothesis. 

Fig. 31. Limits of flammability of hydrogen-carbon dioxide-air and hydrogen-nitrogen-air mixtures at 25°C and atmospheric pressure.

Table V. Limits of Flammability of Hydrogen in Various Oxidants at 25 C and Atmospheric Pressure...

The effect of temperature on the lower limit of flammability of hydrogen in air may be obtained from Equation (4.9). Thus, we have... 

Pressure appears to have little effect on the limits of flammability of hydrogen in air. Coward and Jones report a slight decrease in the flammable range at pressures between 1 and 10 atm followed by a gradual increase at pressures to 210 atm. However, the author and his co-workers found the limits to be essentially independent of pressure between approximately 1 and 8 atm. 

The flammability of hydrogen is simply an expression of the fact that it is an energy carrier. As such, it has been used for a long time, for example as an important constituent of so-called town gas. 

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