The generation of dust occurs in many bulk materials handling applications, including during free-fall, material impact on conveyor transfers, or impact with other materials. Dust has potentially serious consequences to the surrounding environment as well as workers and nearby communities. Companies need to identify and quantify the dust being generated so they can find ways to reduce or eliminate this dust generation. Dustiness testers are one method which can be used to quantify dust generation. This paper investigates the experimental material flow and the subsequent discrete element method (DEM) simulation in the rotating drums of two dustiness testers: the European Standard dustiness tester and the Australian Standard dustiness tester. Preliminary comparisons of the rotating drum designs were undertaken using particle/bulk parameters of polyethylene pellets, a granular "non-dusty" material to investigate the flow behavior, to provide a reference base to compare equivalent simulations and subsequent analysis. A calibrated DEM material model for polyethylene pellets was generated via experimental comparison. Investigations of the rotational speed, volume, and initial loading location of product sample have been performed. The motion of particles in the simulated rotating drums has been compared to visual observation from experimental testing.