The DP-049® CEM Dilution Probe is designed to function as a sample conditioning and transport system to perform four critical functions to prepare the sample from the stack (duct or process) so that it can be measured accurately and precisely by the analyser (typically an “ambient level” analyser). The system uses an air driven eductor which extracts a continuous and precise low-flow sample from the source gas stream. It is then passed consecutively through a coarse and fine particulate filter, a preselected glass or metal orifice, and diluted with the motive air within the probe eductor. This process has now reduced the dew point of the source gas sample to below that of the ambient air. It prepared the often warm, wet, sticky and particulate laden sample, so that it can be transported (at a positive pressure) via an unheated umbilical line to the analyser, up to 100M away.