What is vacuum pump oil?

Vacuum pump oil is a hydro processed, viscous oil solution that acts as a blotter and a moisture absorber in a classic vacuum pump system. The oil is often clear in color, so as to quickly alert the user to the presence of contaminants and non-condensable substances in the solution.

Vacuum pumps are utilized to remove gas molecules from an enclosed space in order to make a partial vacuum. They are used in place of electrical systems in many aircraft flight instruments and are also used in sewage systems, freeze drying, fusion research and uranium enrichment. If the oil in a vacuum pump becomes saturated with contaminants, the pump's effectiveness is severely diminished.