Due to guidelines issued by government health bodies, concerns over personnel safety, and a desire to maintain the quality of manufactured products, containment is becoming increasingly important in a growing number of different industrial contexts. By isolating hazardous materials, a containment system should reduce to acceptably low levels the potential dangers posed to human health and the surrounding environment. During manufacturing processes, it should also assist in the protection of these materials from outside contamination. In this paper, a ventilated containment booth at a pharmaceuticals plant is analysed. This booth is used to contain active powders whilst they are tipped into a reactor for drug manufacture. Experimental data regarding the air hows within the system is compared with numerical predictions generated using computational fluid dynamics (CFD). The agreement is good and the predictions highlight the flow dynamics of the system. The use of CFD is then extended to provide indicators of containment performance for a range of different operational characteristics. These indicators, based on the ventilation performance of the system, and on the ability of the air flow at the hatch face to isolate hazardous materials from the working environment, clearly show the deficiencies associated with the current system. However, they also indicate that certain modifications to the location of the extraction ducting and the rate of air extraction could yield substantial benefits in terms of the overall containment performance of the device.