<P> Since natural gas is a mix of various molecular species, chiefly methane but with varying proportions of other gases, a standard cubic foot does not represent a precise unit of mass . </P> <P> Converting between standard volumes is not always straightforward . For example, converting standard cubic feet to standard cubic meters (SCM) does not use the same ratio as converting cubic feet to cubic metres (1 cubic foot = 0.0283168466 cubic metres) because the standard temperature and pressure used are different . A standard cubic foot (using the convention of 14.73 psi and 60 degree F) is equivalent to 0.0283058557 standard cubic meters (using the convention of 101.325 kPa and 15 degrees Celsius). </P> <P> In the natural gas industry where quantities are often expressed in standard cubic feet, large multiples of standard cubic feet are generally not expressed with Metric prefix, rather with prefixes based on roman numerals where the s for "standard" is often omitted . Common units of gas volumes include ccf (hundred standard cubic feet), Mcf (thousand standard cubic feet), MMcf (million standard cubic feet), . The M refers to the Roman numeral for thousand, two M's would be one thousand thousand, or one million . Bcf (billion standard cubic feet), Tcf (trillion standard cubic feet), Qcf (quadrillion standard cubic feet), etc. are also used . </P> <P> An actual volume can be converted to a standard volume using the following equation: </P>

What is the difference between scf and ccf
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