The document is intended to support EPA's Exposure Assessment Guidelines by providing data and information on standard factors that are used to calculate human exposure to toxic substances. Statistical distributions or ranges of values were developed for body weight, skin surface area, and ventilation rates. Percentile distributions of body weight were computed from the Second National Health and Nutrition Examination Survey (NHANES II) data base using a computer program that performs variance estimation of multistage sample data using the Jack-knife Repeated Replicate approach. Distributions of skin surface areas were similarly calculated from NHANES height and weight data by applying regression equations that were either located in the literature or were developed by multi-variate analysis of available measurements. Insufficient data precluded the development of distributions of ventilation rates. Minimum, maximum, and mean values of minute ventilation at three activity levels were calculated from available measurements. Activity pattern information is presented to permit the calculation of time-weighted average ventilation rates.

"EPA 600-8-85-010." "August 1985." "PB85-242667." Includes bibliographical references. Final report. Funded wholly or in part by the United States Environmental Protection Agency. Contract Number: 68-01-6775 and 68-01-3997. Print reproduction.