For Private Well water sampling, the most common testing is for bacteria, which can be done as an "official" sample, taken by an EPHS, or an "unofficial" sample, taken by the homeowner. Both of these require that official containers, provided by the Missouri State Public Health Lab and available through the local health department, and proper procedures be used when obtaining these samples from the source. There are other types of tests possible for private wells and homes, which include limited inorganic components such as lead, nitrites, and a "new well series", among others. These would require a different type of container and protocol that may include a 6 to 8 hour retention time, where the water would not have been turned on or used at the test premises in that time frame, and are most commonly obtained by an EPHS.