Natural gas - Determination of composition with defined uncertainty by gas chromatography - Part 5: Determination of nitrogen, carbon dioxide and C<(Index)1> to C<(Index)5> and C<(Index)6+> hydrocarbons for a laboratory and on-line process application using three columns (ISO 6974-5:2000); German version EN ISO 6974-5:2001— 20 стр.
Natural gas - Determination of composition with defined uncertainty by gas chromatography - Part 4: Determination of nitrogen, carbon dioxide and C<(Index)1> to C<(Index)5> and C<(Index)6+> hydrocarbons for a laboratory and on-line measuring system using two columns (ISO 6974-4:2000); German version EN ISO 6974-4:2001— 16 стр.