The EPA has clear data collection protocols for evaluating

Last updated: 4/6/2023

The EPA has clear data collection protocols for evaluating the safety of drinking water To assess whether and how deviations from that protocol may affect data the EPA selected a random sample of 32 homes in Chicago and collected water vials to determine water lead levels in mcg l Chicago was used for the study because it is an old city with lead water pipes For each house a vial of tap water was collected first thing in the morning on two different random spring days On one day people were told to use the house as normal on the other day they were instructed to flush all house tabs for five minutes the night before Lead levels were significantly higher on average with normal use than with pre flushing statistical inference 1 Who or what are the individuals units in this study homes in Chicago 2 What type of study is this a case control observational