Oxygen analyzers play an important part in the safe production of pharmaceuticals. With the bulk use of powders and solvents the risk of an explosion is great, therefore a blanket gas (typically N2) is used to replace the air in the process. This removes one element of the fire triangle (oxygen), increasing the safety of the process.
In many petrochemical plants nitrogen is used as a blanketing gas to create an inert atmosphere for safety reasons. Storage tanks in particular contain vapour above the liquid level that is highly flammable, and could easily explode if exposed to a heat source or static electricity. In order to prevent this happening the oxygen level must be maintained below the LEL.
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