As pharmaceutical compounds become more potent and pose a greater challenge from a containment perspective, greater efforts are required to assess the performance of a containment device before introduction to the workplace. Hollett et al (1990) have assessed the containment capability of a glove bag in the context of asbestos removal. However, while data from other industries suggest that the containment capability data for flexible systems are directly comparable to rigid systems, these data are company-specific and are therefore not widely available (exceptions include the data of Lloyd and Wizimirski, 2001). It is likely that flexible containment provides other operational advantages apart from containment, e.g. time and labour savings, over rigid systems, but these have not been formally assessed. To redress this, the objective of the present study was to carry out an assessment of both the ergonomic and containment capability aspects of two glove bag designs to be used as the primary containment device for the unit operation of changing product-contaminated wet and dry cartridge filters.