The evaluation or design of a granular material handling process requires reliable data if executive decisions are to be made. Material behavior in a given process is usually investigated by collecting and analyzing material samples from different locations within the system. However, sampling can be a significant source of errors, as a poor sampling method can lead to measurements not truly representative of the real process. This paper highlights some sampling issues in assessing particle degradation in dilute phase pneumatic conveying systems. Experimental data of particle degradation measured in a pilot sized industrial pneumatic conveyor are compared to the outcomes of a complete degradation toolkit, combining a laboratory scale degradation tester and a computational model. This comparison is used to illustrate the fact that an incorrect sampling procedure may result in misleading and doubtful experimental information associated with a high uncertainty level.