View source for Volume units used in petroleum engineering

{{refimprove|date=September 2012}}

Several units of volume are used in [[petroleum engineering]].

==Units==

{| class="wikitable"
!colspan="2"|Unit!!Thousand!!Million!!Billion (10<sup>9</sup>)
|-
|[[cubic meter]]||m3||E3m3 (sometimes referred to as a "dec") ||E6m3||
|-
|[[Barrel (volume)|barrel]]||bbl||Mbbl||MMbbl||
|-
|[[Standard cubic feet]]||scf||Mscf||MMscf||Bcf
|}

Due to the risk of confusion with the SI convention where the "M" prefix stands for "mega" representing million, the [[Society of Petroleum Engineers]] recommends in their style guide that abbreviations or prefixes M or MM are not used for barrels of oil or barrel of oil equivalent, but rather that thousands, millions or billions are spelled out. <ref>{{cite web |title=Style Guide |url=https://www.spe.org/media/filer_public/6b/b7/6bb70153-56c9-4e9b-9f8c-502da8c2054e/style_guide_2022.pdf |publisher=Society of Petroleum Engineers |access-date=13 December 2024}}</ref>

==Conversion factors==
*Oil conversion factor from m³ to bbl (or stb) is 6.28981100
*Gas conversion factor from standard m³ to scf is 35.314666721

Note that the m³ gas conversion factor takes into account a difference in the standard temperature base for measurement of gas volumes in metric and imperial units. The standard temperature for metric measurement is 15&nbsp;degrees Celsius (i.e. 59&nbsp;degrees Fahrenheit) while for English measurement the standard temperature is 60 °F. Gas undergoes a slight expansion when the temperature is raised from 15 °C (59 °F) to 60 °F and this expansion is built into the above factor for gas.

The ''standard'' temperature and pressure (STP) for gas varies depending on the particular code being used.<ref>A good discussion can be found on http://www.chemeurope.com/lexikon/e/Standard_conditions_for_temperature_and_pressure/</ref> It is just as important to know the standard pressure as the temperature. Formerly, OPEC used 101.325 kPa (14.696 psia) but now the standard is 101.560 kPa (14.73 psia).

==References==
{{reflist}}

[[Category:Petroleum engineering]]