CALtec - Backflow test equipment sales, service, and calibration. www.cal-tec.org
Chicago Backflow Prevention Systems, Inc. - Provider of cross-connection control with certified, licensed backflow prevention professionals. www.backflow.com/open.htm
Kansas City Backflow - ASSE certified school for backflow tester certification and re-certification. Offers regularly scheduled training classes and testing in Kansas City, Missouri. www.kcbackflow.com
