23 Apr I’m developing the requirements for a medical product, nitrogen gas system. Should I plan on using electropolished stainless steel components?
It depends on the purity requirement. Do you have a ppm or ppb purity requirement? Is there point of use filtration and/or purification? In general, if the allowable contaminants at the point of use are in the ppb range or less, then electropolished tubing and components are recommended. If the range is ppm for contaminants, then non-electropolished is probably suitable. System capacity and tube run length could also influence the decision. For low capacity and short run length, the cost premium for electropolished won’t be great so if there is any uncertainty in the allowable contaminant level, electropolished will alleviate concerns.
Keep in mind that a system specification should be crafted to the application. For example, with gas regulators, some non-electropolished regulators are very low quality and can introduce hydrocarbons into the gas stream. One needs to look at all parts of the system to be certain it will perform as required.
The following link provides more detailed information on determining the need for electropolished stainless components in high purity gas systems: https://www.criticalsystemsinc.com/high-purity-gas-systems-and-electropolished-EP-components