OR Plumber study plan

Define the five domains in your own words and list the percentage weight each carries so you can budget study time accurately.

Build a one-page reference sheet of core plumbing terminology (fixture unit, trap seal, developed length, air gap, backflow, water hammer) with a plain-language definition for each.

Locate the current Oregon Plumbing Code adoption and identify which model code edition and state amendments it is based on.

Outline how Oregon's plumbing statute, administrative rules, and adopted code fit together, naming the agency that enforces them.

Explain the purpose of a trap and how trap seal depth is measured and protected.

Differentiate between a vent's role and a drain's role using two real fixture examples.

Identify common pipe materials (copper, PEX, CPVC, PVC, ABS, cast iron, galvanized steel) and state one approved use and one limitation for each.

Describe how slope, pipe sizing, and fixture units relate when sizing a drain line.

Trace water from the meter or private supply through the service line, main, riser, and branch to a fixture.

Explain the difference between a direct and an indirect water supply connection and give an example of each.

Describe how pressure, elevation, and friction loss affect flow at an upper-floor fixture.

List the components of a typical backflow prevention assembly and state where each is required.

Identify the components of a DWV system (soil stack, waste stack, vent stack, stack vent, branch, trap arm) on a diagram you draw yourself.

Explain how a vent protects a trap seal and describe what happens to the seal when a vent is blocked.

Compare wet venting, common venting, and individual venting, noting where each is permitted.

Calculate the developed length of a simple drain run and apply the correct slope for the pipe size.

Match at least ten common fixtures (water closet, lavatory, kitchen sink, bathtub, shower, floor drain, hose bibb, dishwasher, clothes washer, water heater) to their fixture-unit values.

Describe the installation requirements for a water closet flange, a shower pan, and a floor drain trap primer.

Explain the difference between a fixture's minimum supply and its drainage requirement.

Identify the clearance and accessibility requirements that apply to fixtures in residential settings.

Read the Oregon Plumbing Code sections on permits and inspections and summarize who may pull a permit and when an inspection is required.

List the licensing requirements for plumbers in Oregon, including apprentice, journeyman, and master categories.

Describe the penalty and enforcement provisions that apply to unpermitted or noncompliant work.

Identify Oregon-specific amendments that differ from the model code, focusing on at least three you can state precisely.

Apply code sections to three realistic scenarios (adding a bathroom, replacing a water heater, extending a drain) and write the permit and inspection steps for each.

Recheck your DWV diagram against the venting sections and correct any violations you find.

Practice locating answers in the code by index rather than memory, timing yourself on ten lookups.

Review Oregon's rules on backflow prevention and cross-connection control as they apply to the scenarios above.

Take one full-length timed practice exam and record your score by domain.

Re-study your two weakest domains using the terminology sheet, diagrams, and data sheets you built in earlier weeks.

Recite from memory the fixture-unit values, slope rules, and trap seal requirements without notes.

Build a final one-page cheat sheet of numbers, thresholds, and Oregon-specific rules to review the morning of the exam.