Mass Flow Controllers (MFCs) are used in many applications that require different certification requirements for materials that could come into contact with anything going into the end product. For gas control in bioreactors, gas is being controlled by MFCs in a gas box, in open frame systems, or mounted on a skid. Process gasses go through the MFC and into the bioreactor to control the cell growth and cannot be contaminated by the materials in the gas supply components.