This report covers the investigation of possible alternative methods to measure the volatility of heavy crude oil. The work was restricted to a literature search and inquiries made to informed government and industry groups. The current method for determining vapor pressure at storage temperature for crude oil and refined petroleum products involves determination of Reid Vapor Pressure and use of a correlation nomograph. The technique is not applicable to some heavy crudes. Also, there can be an undue influence from methane and ethane. Alternative methods investigate include developing data to extend the temperature and vapor pressure range of the correlation nomograph, modifying the Reid Vapor Pressure Method, use of a vapor composition approach, and determining evaporation losses under controlled conditions. Sampling and analytical problems were evaluated for the alternatives. A recommendation was made to conduct further studies on the vapor composition method.

"December 1981." "EPA 909/9-81-004." "Contract No. 68-02-3509." "Work Assignment No. 11." Final report.