A wide variety of specialty gas mixtures are required in industrial, R&D, laboratory, and many other processes. Manufacturing specialty gas mixtures begins with the prep and surface treatment of the cylinders for the specific gas mixture to ensure quality and accuracy. For example, cylinders that are going to be used with gases that are reactive (HCL, NO2, H2S, etc.) even in small concentrations must be specially treated. Gases to be used in specialized blends must also be adequately pure for the mixture before the blending process.

Blending of gases is generally done in three ways: gravimetric, volumetric, and dynamic blending. Gravimetric is the most precise of the three methods of blending and is done with extremely sensitive gravimetric scales and must be rigorously analyzed after blending to detect impurities. The manufacturing process must also be carefully monitored along the way, with oxygen being one of the impurities measured to ensure ambient air hasn’t gotten into your mixture at any stage.

The OMD-675 and OMD-677 provide in-line oxygen measurements down to levels as low as the 0-1 ppm O2 range to constantly monitor the gas during the process for impurities. The OMD-640 provides the same accuracy in a portable package, allowing for spot-checking of the final product once it reaches the cylinder for one final purity check before it is sent to the customer.