The Backflow (PL30) Contractor License allows you to maintain and repair existing backflow prevention assemblies.
The Washington Backflow (PL30) Contractor License may not install new backflow prevention assemblies or replace any of its parts
Login credentials emailed upon enrollment
Unlimited access (no time limits)
Lecture videos
Practice questions
Key concepts
Step-by-step solutions to math problems
Live review
classesBelow is all the information related to the trade exam, including the official reference list.
Candidates must apply for eligibility with the Department before being allowed to take the examination. Please note that this is a closed-book examination.
This set of books includes all required references for the Backflow (PL30) exam. Orders placed before 2 PM are shipped the same day via UPS and a tracking number is emailed before 3 PM.
Books Not Allowed in Testing
NFPA 99C Gas and Vacuum Systems
Uniform Plumbing Code with the Washington Sta