Maximum Air Pressure. This number refers to the maximum amount of air you can put in a tire before you harm it. It is not the recommended tire pressure; that number can be found in your owner's manual and on the doorjamb. Traction Rating. A traction rating can also be found on the sidewall of all modern tires.
Reid vapor pressure. Reid vapor pressure (RVP) is a common measure of the volatility of gasoline. It is defined as the absolute vapor pressure exerted by a liquid at 37.8 Â°C (100 Â°F) as determined by the test method ASTM-D-323.
The term vapor pressure usually refers to equilibrium vapor pressure, or the pressure at which the rate that particles leave the substance to form vapor equals the rate that particles reenter the substance from the vapor. Vapor pressure depends only on the temperature and the type of substance. Scientists can measure the temperature and vapor pressure of an unknown substance to help determine what it contains. Scientists usually measure vapor pressure in units of atmospheres (atm), millimeters of mercury (mm Hg), or torr.