In this article, I present the major issues associated with obtaining a representative sample in NG applications. The article explains what is representative sampling, and why sampling is important in the natural gas industry. I discuss factors that determine what should be a suitable sampling frequency in a process, and which sampling standards can be followed to ensure representative sampling.

Several major issues in obtaining a representative sample, and common design flaws that lead to poor sampling are presented and discussed. In addition, I present how a suitable probe length can be determined and how the probe should be installed. The different types of commonly used sampling probes are also compared and discussed.