OR Plumber study guide

OR Plumber · Work through your exam, one topic at a time.

The Oregon Plumber licensing credential is administered within Oregon's Building Codes Division (BCD), part of the Department of Consumer and Business Services. The BCD is the state body that handles licensing, code programs, permits, and continuing education for trades in Oregon. The OR Plumber study guide has 5 sections and about 1,896 words.

General Plumbing Knowledge

This domain tests the vocabulary, materials, and basic physics that the other four domains assume: which pipe materials may carry potable water, how joints are made, how pipe is supported, and how pressure, elevation, and fixture units relate. Questions usually ask you to choose a material or predict a pressure, not just define a term.

382 words, about 2 min 02

Plumbing Systems and Fixtures

This domain tests fixture selection, maximum flow rates, clearances, and installation details - the parts of the trade an inspector can see and measure. Expect questions on fixture units, trap sizes, accessibility dimensions, and what must be installed under a shower or around a water closet.

354 words, about 2 min 03

Water Supply and Distribution

This domain tests how potable water is sized, pressurized, protected, and delivered. Questions focus on minimum and maximum pressures, service sizing, backflow protection, thermal expansion, and the difference between static and flowing pressure.

332 words, about 2 min 04

Drainage, Waste, and Vent Systems

This domain tests gravity drainage and venting: slope, sizing, traps, trap arms, vents, cleanouts, and testing. Most failures here come from measuring the wrong distance or venting a trap incorrectly.

410 words, about 2 min 05

Oregon Plumbing Code and Regulations

This domain tests Oregon law and administration rather than trade technique: which code applies, who may do the work, what permits and inspections are required, and where Oregon amends the model code. Oregon plumbing law is in ORS chapter 447, with administrative rules in OAR chapter 918.

418 words, about 2 min