"Reid Vapor Pressure" is a pressure determined by a conventional analytical method for determining the vapor pressure of petroleum products. In essence, a liquid petroleum sample is introduced into a chamber, then immersed in a bath at 100.degree. F. (37.8.degree. C.) until a constant pressure is observed. Thus, the Reid Vapor Pressure is the difference, or the partial pressure, produced by the sample at 100.degree. F. (37.8.degree. C.). The complete test procedure is reported as ASTM test method D 323-89 in the 1990 Annual Book of ASTM Standards, Section 5, Petroleum Products, Lubricants, and Fossil Fuels.
- From U.S. Patent No. 5,288,393 on reformulated gasoline, at http://220.127.116.11/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1='5288393'.WKU.&OS=PN/5288393&RS=PN/5288393