Pesticides applied indoors vaporize from treated surfaces (e.g., carpets and baseboards) resulting in elevated air concentrations that may persist for long periods after applications. Estimating long-term respiratory exposures to pesticide vapors in residential indoor environments using active (pump-based) sampling systems has been costly and burdensome on occupants. Diffusion-controlled passive sampling devices (PSDs), which do not require a noisy pump and can be situated unobtrusively within the home, would offer distinct advantages. The U.S. EPA is investigating the applicability of diffusive PSDs, semipermeable membrane devices (SPMDs), solid-phase microextraction (SPME), and other gas-sorbent partitioning samplers for estimating sermivolatile organic compound (SVOC) pesticides in homes. This paper presents the results of the initial evaluations of two diffusion-controlled PSDs for determination of three pesticides in room air.