Abstract: A fluid medium is used in a process for polishing all surfaces of plastic components made of a material which is insoluble or inert within that fluid medium unless subjected to a temperature at which the insoluble plastic would deform. The process, which is particularly suitable for polishing the internal surfaces of tubing components for medical equipment, includes applying a vaporized solvent at an elevated pressure to liquify or melt the insoluble plastic component surfaces without deforming the component, followed by solidifying or freezing the surfaces by removing the component from the presence of the vapors.