The paper discusses the use of a static chamber with known environmental conditions to study the ability of microorganisms to grow on a variety of building materials, as a first step in the development of prevention and control strategies for biocontaminants in indoor air quality. A series of preliminary studies utilizing these chambers are presented in the paper and demonstrate the potential value of the static chamber design. Initial experiments have been performed evaluating the effect of relative humidity (RH) on ceiling tile blocks of varying moisture content. The data presented here are preliminary results on the use of these static chambers in assessing the effect of five RHs on the ability of Penicillium aragonense to grow on pieces of aged ceiling tile. Blocks in the 97 percent RH chamber with an equilibrium moisture content of about 5 percent yielded an increase of microorganisms by two orders of magnitude within 14 days.