Full Description

1.1This test method covers the use of automatic vapor pressure instruments to determine the vapor pressure of liquefied petroleum gas products at a temperature of 37.8C, vapor to liquid ratio of 0.5:1, and pressures from 200kPa to 1550kPa on a sample volume of 3.33mL.

1.2This test method is applicable to the determination of vapor pressures of liquefied petroleum gas products at temperatures from 37.8C to 70C, vapor to liquid ratios of 0.1:1 to 4:1, and pressures up to 3500kPa; however, the precision of the test method (see Section 15) has only been determined for a vapor to liquid ratio of 0.5:1, at a temperature of 37.8C, and a pressure range from 300kPa to 1500kPa.

Note 1:This test method is not intended to determine the true vapor pressure of LPG samples, but rather determine and report the vapor pressure of LPG at the 37.8C temperature and 0.5:1 vapor to liquid ratio as the Test Method D1267 method.

Note 2:This test method is not a true vapor pressure method and will not measure the full contribution from any dissolved gases such as nitrogen or helium if they are present. The contribution of light gases to the measured vapor pressure is highly dependent on the test temperature, type of gas, and V/L ratio of the test.

1.3The values stated in SI units are to be regarded as standard.

1.3.1Exception-Non-SI units are included in parentheses for information only.

1.4This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific warning statements, see Appendix X2.