The specific purpose of this bulletin is to recommend procedures for sampling natural gas for subsequent analysis by gas chromatography. This bulletin describes procedures for obtaining representative "spot" samples of natural gas from vacuum or pressure sources in containers which are suitable for transporting the sample to a laboratory. Containers must be selected so that the gas composition is not altered for the tests to be performed during storage or transportation of the sample. These sampling procedures should be applicable for most situations normally encountered in natural gas sampling. The procedures described in this bulletin may be used for obtaining samples for analysis by methods other than gas chromatography. Some of the procedures described in this bulletin are suitable for sampling "wet" (rich) natural gases at pressures up to 1100 psig. There are no pressure restrictions in sampling "dry" (lean) natural gases. Both a sample probe and a GPA separator must be used to obtain good, representative samples.