Well just completed and passed a full week of brutal backflow testing certification. I want to highly recommend this certification which follows University of Southern California procdedures for testing. Mandatory backflow testing is starting to happen quickly here in our New England states and we as irrigation contractors need to take the respondsabilty to educate the consumer why we install that ugly expensive piece of brass on the side of their house and how important it is to have it checked atleast annually. And of course its a profiting new service not only for our irrigation devices but for all testable backflows around As for the class- It is very technical and lots of reading and hands on 5 different types of devices. I recommend if anyone looks into it - BE SURE to dedicate a full week of no interuptions of work. Out of 24 guys in the class I saw atleast 10 Master Plumbers fail- These were the guys that were on their cell phones every 5 minutes.