The first thing a sample conditioning box (SCB) needs to do is get the sample to the sensor. If the gas at the measurement point is stagnant, or at too low of a pressure, the SCB will use either a mechanical pump, or a venturi type of eductor, to create a flow that will overcome pressure losses of the filters and other devices and pull the sample to the sensor.
Next, the sample needs to be temperature conditioned; typically, cooled to a level safe for the sensor. It will also be dried, filtered through different size meshes to remove particulates, and may even go through an acid scrubber to remove corrosive chemicals. Due to all the possible different conditions a sample can be in, a SCB needs to be sized and designed individually for the process it is used in. The one-size-fits-all approach does not work well and could waste money.