Carl explains.

Ability of lubricating oils to release entrapped air (German: Luftabscheidevermögen, LAV). Important property in gear oils and hydraulic fluids to prevent foaming problems. The air-release property of an oil indicates the velocity of releasing dispersed air bubbles which influence the compressibility of the fluid and cause malfunctions in hydraulic systems. The air-release capacity is determined according to the Impinger method.

The BECHEM lubricant ABC explains more than 400 technical terms. On the web and with an app.