 Respondents are asked to report the frequency and timing and location of exposures, detailed information about the amount of water swallowed and head submersion, and basic demographic characteristics such as age, gender, socioeconomic status and family composition.Once sufficient data are collected and determined to be representative of the general population, they are usually fit with distributions, and these distribution parameters are then used in the risk assessment equations.Monitoring data representing occurrence of pathogens, direct measurement of pathogen concentrations, or estimations deriving pathogen concentrations from indicator bacteria concentrations, are also fit with distributions.