ASTM D 2598:2021

1.1 This practice covers, by compositional analysis, the approximate determination of the following physical characteristics of commercial propane, special-duty propane, commercial propane/butane mixtures, and commercial butane (covered by Specification D1835 ): vapor pressure, relative density, and motor octane number (MON). 1.1.1 This practice is not applicable to any product exceeding specifications for nonvolatile residues. (See Test Method D2158 .) 1.1.2 For calculating motor octane number, this practice is applicable only to mixtures containing 20% or less of propene. 1.1.3 For calculated motor octane number, this practice is based on mixtures containing only components shown in Table 1 . 1.2 The values stated in SI units are to be regarded as standard. 1.2.1 Exceptions: 1.2.1.1 Non-SI units in parentheses are given for information only. 1.2.1.2 Motor octane number and relative density are given in MON numbers and dimensionless units, respectively. 1.3 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

75.160.30