It is defined as the absolute vapor pressure exerted by the vapors of the gasoline at 37.8 °C in a volume of air 4 times the volume of liquid.
It is the measure of volatility and vapor lock tendency of motor gasoline fuel. Sufficient RVP is needed in order to facilitate the starting of an internal combustion engine.
This property measures the vapor-lock tendency of motor gasoline in which excessive vapors are produced in the fuel line causing interruption of the supply of liquid fuel to the engine.
It also indicates the explosion and evaporation hazards of the fuel. ASTM D-323 is a standard method to measure the RVP in the laboratory.