As part of the Total Human Environmental Exposure Study (THEES), a self-administered questionnaire was developed to identify sources of exposure to BaP and PM-10. Thirteen participants in ten households completed a daily personal activity log for fourteen consecutive days during January 1988. Validation of the instrument was obtained in three ways: internal questionnaire checks, comparison with pre-sampling estimates of time/activity patterns, and comparison with earlier studies. The log was found to be easy for participants to use and reliable in most of its questions. Effectiveness of the log in identifying sources of exposure was enhanced by having most responses in the form of continuous variables. While most of personal exposure to both BaP and PM-10 could be attributed to outdoor sources, a variety of household sources and personal activities were also identified. Higher levels of PM-10 were associated with use of unvented kerosene space heaters and coalstoves, stove-top cooking, ETS, and house cleaning. Personal exposure to BaP was primarily associated with ambient levels, and secondarily with ETS, coalstove use, and cooking activities.