The journeyman plumber exam today

Maya Chen had a few hundred hours left before she met the experience requirement for a journeyworker plumber license in Columbus. She had roughed in Kingsway Tower, commissioned the hospital wing's medical gas lines with Daniela, and spent six months on the service trucks with Grace Lin. The last step was the exam. Luis Ferreira, who had supervised her since her first week at Northbridge Mechanical, put a code book bristling with tabs on the lunchroom table. "Twenty-two years ago I took this exam," he said. "I passed by four points. I knew the work. What I didn't know was the exam. We are going to fix that for you."

This course is the final plumbing course in the program. It combines a second pass through the plumbing code, harder sizing problems that join several code tables into one answer, and a structured review of everything from PLB-110 to PLB-420. It also teaches the exam as a task in its own right: how the questions are built, how the content outline tells you where to spend study time, how to find answers in the code book under time pressure, and how to turn every practice mistake into a lesson. By the end, Maya takes the exam. You will follow her plan and build your own.

What the journeyman exam is

In Columbus, Ohio, plumbers who work under the city's building permits need a city license. The journeyworker plumber license requires five full years of plumbing experience, each year being twelve consecutive months with at least 1,600 hours of work, or completion of a certified US Department of Labor apprenticeship program. The applicant must also pass the National Standard Journeyman Plumber written exam, known by its code F25, which is delivered by the International Code Council. Contractor licensing in Ohio is a separate step handled by the state's construction industry licensing board, which Maya will meet later in her career.

Luis made the point early: the F25 is a code exam first. Its questions are written against the International Plumbing Code edition named in the candidate bulletin, and almost every question can be answered from the book. That is good news and bad news. The good news is that you do not have to memorize table values. The bad news is that the exam gives you about two and a half minutes per question, and a candidate who cannot find the right section quickly runs out of time. The Ohio Plumbing Code is based on the 2021 IPC, so the book you use on the job and the book on the exam are closely related.

The format in numbers

The F25 exam has about 70 multiple-choice questions, each with four options and one correct answer, and the time allowed is about three hours. It is open book: candidates bring the code edition listed in the candidate bulletin, and may usually tab and highlight it within the bulletin's rules, but may not add loose notes or written pages. The pass mark set by the city is 70 percent. A passing score expires after one year if no license application is filed. Applications go to the city's Skilled Trades Review Board, which meets monthly, and must be in at least one week before the meeting.

The questions are of three kinds. Lookup questions ask for a single value from the book, such as the minimum size of a vent for a given drain. Interpretation questions ask whether something complies, which needs a definition and a rule read together. Plan-reading and calculation questions give a drawing, a fixture schedule or a riser and ask for a size, a fixture count or a load. The plan-reading share is large, which is why this course spends whole lessons on sizing problems that use several tables at once.

Turning the numbers into a pacing plan

Before Maya opened a single practice question, Luis had her work out what the format meant for her time. The plan she wrote on the first page of her study notebook has two parts: the average time she can give each question, and the number of correct answers she needs to pass.

The figure of 21 wrong answers changed how Maya thought about the exam. She had been afraid of the plan-reading questions. Luis pointed out that if she got every direct lookup right, she could miss several hard questions and still pass. The reverse was not true. Losing easy marks to slow searching, or to reading the wrong table, is what fails candidates who know the trade.

A pacing plan only works if it is checked during the exam. Maya set checkpoints: after each quarter of the time, she should be at least a quarter of the way through the questions. Luis wrote a short program to print the checkpoints for any exam length, which she later used for every practice test.

# Exam pacing checkpoints
import math

questions = 70       # F25 journeyman plumber exam (about 70 questions)
minutes = 180
pass_mark = 0.70
review_min = 20      # time kept for a final review pass

first_pass = (minutes - review_min) / questions
need = math.ceil(pass_mark * questions)
print(f"Average per question: {minutes / questions:.2f} min")
print(f"First-pass budget:    {first_pass:.2f} min ({first_pass * 60:.0f} s)")
print(f"Correct answers needed: {need} of {questions} ({questions - need} may be wrong)")
print()
print("Checkpoint   Elapsed   Should have answered")
for frac in (0.25, 0.5, 0.75, 1.0):
    elapsed = (minutes - review_min) * frac
    done = round(questions * frac)
    h, m = divmod(round(elapsed), 60)
    print(f"{int(frac * 100):>5d} %     {h}:{m:02d}      {done:>4d}")
print(f"Review pass  {(minutes - review_min) // 60}:{(minutes - review_min) % 60:02d}-{minutes // 60}:00   flagged questions only")

Average per question: 2.57 min
First-pass budget:    2.29 min (137 s)
Correct answers needed: 49 of 70 (21 may be wrong)

Checkpoint   Elapsed   Should have answered
   25 %     0:40        18
   50 %     1:20        35
   75 %     2:00        52
  100 %     2:40        70
Review pass  2:40-3:00   flagged questions only

Change the numbers at the top to match any practice test. A twenty-question quiz with a 40-minute limit gets the same treatment, and practicing with checkpoints on short tests makes them automatic on the real one.

Eligibility, applying and the day itself

Maya's path to the exam ran through two offices. The exam itself is scheduled through the International Code Council's testing service, by searching for the F25 exam, and can be taken at a test center or, where offered, through remote proctoring. The license application goes to the city, with proof of experience: either a completion certificate from a USDOL registered apprenticeship or documentation of five years at 1,600 hours or more each. The candidate bulletin for the exam lists the allowed code edition, the identification rules and what may be written in the book. Maya read it twice, because a book with prohibited notes can be refused at the door.

Luis gave her a list for the day itself, and she taped it inside her notebook:

• Sleep properly the two nights before. Fatigue costs more marks than one more evening of study gains.
• Bring the identification the bulletin asks for, the approved code book, and nothing that is not allowed in the room.
• Arrive early enough to find the room, the washroom and a seat without rushing.
• Read the instructions on the screen or the paper calmly. Check how flagging, moving between questions and submitting work before starting.
• Start the clock on your pacing plan, and check it at each checkpoint.

What happens after

A passing score goes to the city with the license application, and the Skilled Trades Review Board decides the application at its monthly meeting. The score is good for one year, so Maya planned to file within weeks of passing. A candidate who does not pass gets a score report by content area, which is the most useful study document they will ever get, and can retake after the waiting period the testing service sets. Luis had seen good apprentices fail once and pass comfortably the second time, after using that report to aim their study.

Luis also gave her a reason to take the exam seriously that had nothing to do with marks. A certified plumber signs off work that protects drinking water, keeps sewer gas out of homes and carries hot water and gas safely. The exam is how the public knows that the person signing has the knowledge behind the signature. Passing it is the end of an apprenticeship and the start of being responsible for other people's safety without a supervisor checking the work.

How this course is organized

The course follows the order of Maya's study plan. Lessons 2 and 3 set up the tools: how the exam blueprint maps onto study time, and how to navigate the code quickly. Lessons 4 to 6 are the hard sizing problems: drainage and venting, water supply, and storm drainage with special systems. Lessons 7 to 10 review the rest of the trade in the order of the exam's weightings: gas, hydronic heating and backflow; fixtures, water heaters and services; plumbing math and science; and safety, tools and trade practices. Lessons 11 and 12 are about the exam itself: practice strategy, error logs, full mock exams and the final two weeks.

Every lesson ends with practice questions and a five-question quiz written in the style of the exam: four options, one correct answer, distractors that a partly prepared candidate might choose. The course exam is a twenty-question mock that mixes every topic. Keep your scores and the time each quiz took. By lesson 11 you will analyze them the way Maya did.

Building the habit of the exam

Luis had Maya do one thing every working day from the first week: answer ten practice questions at lunch, with a timer, and write down each one she got wrong and why. It took fifteen minutes. Over twelve weeks, it added up to more than five hundred questions and a notebook that showed exactly where her knowledge was thin. She found, to her surprise, that her weak areas were not the hard sizing problems but hydronic heating, which she had barely touched since PLB-310, and rigging, which she had always left to the foreman.

Small, regular practice beats long cramming sessions for three reasons. Spacing the same topic over weeks makes it stick far better than repeating it in one evening. Answering questions, rather than rereading notes, forces the brain to retrieve the knowledge, which is the skill the exam tests. And timing every set builds a feel for pace that no amount of reading can give.

Maya also joined a study group with two other apprentices from her related technical instruction class. They met every second Thursday, each brought five questions they had written themselves from a chapter of the code, and they raced each other to find the answers in the book. Writing a good question with three believable wrong answers turned out to be one of the best ways to learn a chapter, because it forced her to know exactly why the wrong answers were wrong.