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The information below will help you complete the application or renewal successfully.


Individuals performing or offering to perform the installation, maintenance, testing, repair, replacement or rebuilding of backflow prevention assemblies must be certified by our agency as either a backflow prevention rebuilder (BF) or backflow prevention tester (BT).

Anyone applying for a new or renewing a certification must provide proof of current ASSE certification. View a list of approved ASSE certification schools.  

Backflow prevention assemblies 

  • backflow prevention rebuilder certification allows the holder, who must also hold a current plumbing license, to perform the installation, maintenance, testing, repair, replacement or rebuilding of backflow prevention assemblies. Current ASSE 5130 and 5110 certification is required for this registration.

  • backflow prevention tester certification limits the holder to testing backflow prevention assemblies. A plumber license is not required to obtain a tester certification, though current ASSE 5110 certification is required.

Individual backflow certification renewal schedule

Individuals who have a master plumber license that expired Dec. 31, 2014, will have to submit proof of ASSE 5130 and 5110 certification to renew their backflow prevention rebuilder or will require proof of ASSE 5110 certification to renew their backflow prevention tester.

Individuals who have a journeyworker plumber license that expired Dec. 31, 2015, will have to submit proof of ASSE 5130 and 5110 certification to renew their backflow prevention rebuilder or will require proof of ASSE 5110 certification to renew their backflow prevention tester.

Anyone who is not a licensed plumber but holds a backflow prevention tester certification will have to submit proof of ASSE 5110 certification when they submit their BT certification renewal.

Backflow prevention certification application and forms

Questions?

Contact us at 651-284-5034 or dli.license@state.mn.us.