Disinfection of drinking water is one of the major public health advances of the 20th century however the disinfectants themselves can react with naturally occurring materials in the water to form unintended byproducts which may pose health risks. A major challenge for water suppliers is balancing the risks from microbial pathogens and disinfection byproducts. Contaminates are in our water supply some not regulated or adequately controlled posing immediate health problems. People turn on their taps to drink shower bathe cook wash dishes and clothing assuming it is safe. Bacterial contamination causes severe digestive problems fever nausea diarrhea and sometimes even death. According to the EPA total coliform and E. coli bacteria testing is recommended twice a year. Fecal coliform bacteria are mostly found in drinking water that comes from private wells and small water systems. This is partly because private water supplies small rural public water supplies and private wells are not required by law to be tested. The PRO-LAB comes with an Optional Lab Analysis. On the petri dish the test will show columns - if you have 0 - 5 columns indicates clean water. Over 5 columns you should send in for full analysis this kit will need to be mailed inside the included pre-stamped envelope to Pro Lab Inc s. There is a charge of $30 for the testing. Pro Lab Inc guarantees the fastest turnaround time in the laboratory testing industry! This bacteria in water test kit offers two 2 types of analytical methods. The first method simply involves counting the number of colonies that are growing on the petri dish. The second method optional requires sending the petri dish to Pro-Lab for a more detailed analysis $30 lab fee required which will identify the bacteria present in your water. Safe and easy to use.