Increasing Efficiency of Fecal Coliform Testing through EPA-Approved Alternate Method Colilert 18

Poster Presentation

Prepared by

Contact Information:; 757-824-1155


40 CFR Part 136.3 lists 21 SM 9221 C+E as the primary method of determination for fecal coliforms. This method requires a large time and reagent investment for the performing laboratory. In late 2010, the EPA approved an alternative procedure for the determination of fecal coliforms designated as Colilert-18. However, as of late 2016, only two VELAP-certified laboratories in the Commonwealth of Virginia have been certified in this method. A comparison between these two methods will be accomplished through a detailed discussion of the pros and cons of both procedures emphasizing differences in quality control, reagents, time allocations, and the drastic difference in method complexity. The process for certification in the Colilert-18 method will also be covered.