Six timed sections, about 140 questions, roughly two hours, no calculator — and at most locals, your score decides your place in line for a union pipe-trades apprenticeship. Here is exactly what is on the test, how it is scored, and how to walk in with a plan.
The GAN aptitude test is the standardized entrance battery administered by GAN Human Resources on behalf of United Association (UA) locals — the union plumbers, pipefitters, steamfitters, sprinkler fitters, and HVAC-R service techs. Some other trades’ joint apprenticeship training committees (JATCs) use GAN testing as well. Rather than building their own exams, training committees contract GAN HR for a standardized, proctored, legally defensible screening process.
It is not a plumbing or fitting knowledge test. No trade experience is required or assumed. The battery measures the underlying abilities the apprenticeship builds on: careful reading, arithmetic without a calculator, pattern recognition, spatial visualization, and mechanical intuition.
One caveat before anything else: not every local uses GAN. Each training committee chooses its own testing provider — Steamfitters Local 638 in New York City, for example, uses the Wiesen Test of Mechanical Aptitude instead. Your invitation letter describes your test. Read it carefully and let it override anything generic, including this page.
Applicants to union pipe-trades apprenticeships. After you apply to your local’s program and meet the basic requirements (usually 18+, diploma or GED, driver’s license), the training center schedules you for a proctored testing session — photo ID required, phones away, scratch paper provided, strict timing.
The battery runs six separately timed sections — about 140 questions and roughly 120 minutes of testing time in total. Because each section has its own clock, a fast finish in one section cannot buy time for another.
| Section | Questions | Time | What it covers |
|---|---|---|---|
| Reading Comprehension | 42 | 25 min | Short technical passages followed by multiple-choice questions answered strictly from the text. |
| Numerical Computation | 28 | ~21 min | Straight arithmetic: fractions, decimals, and percentages — by hand, no calculator. |
| Numerical Reasoning | 10 | 10 min | Number series — spot the pattern, supply the next number. |
| Problem Solving | 35 | 35 min | Word problems applying arithmetic to practical scenarios: rates, costs, quantities, measurements. |
| Paper Folding | 12 | 15 min | Spatial visualization — a sheet is folded and punched; you pick the correct unfolded pattern. |
| Mechanical Comprehension | 13 | 13 min | Bennett-style diagram questions on levers, pulleys, gears, and fluids — physical intuition, not formulas. |
| Total | ~140 | ~120 min | Multiple choice throughout. No calculator on any section. |
Exact counts and timings can vary slightly by test version — the numbers above reflect the current standard battery. Your invitation letter is the final word.
Every math question on the battery — 28 computation items, 10 series, 35 word problems — is done by hand. That single rule is why prepared and unprepared applicants score so differently. The arithmetic itself is not advanced; doing it quickly and accurately under a clock is the skill being measured. If your fraction and decimal work is rusty, rebuilding that fluency is the highest-return preparation you can do — our study guide covers exactly how.
Here is the honest version. GAN HR scores the battery and reports results to the training committee, which applies its own standards. Most programs use the test in one of two ways:
Either way, most locals order all qualified applicants from highest to lowest and fill apprenticeship classes from the top of that list down. That is the part applicants underestimate: passing is not the goal — ranking high is. A minimum-clearing score can leave you waiting behind dozens of people; a top-tier score can mean a call within weeks. Eligible lists typically stay active for one to two years before a new cycle starts.
Results usually come back within about 60 days. Weightings, cutoffs, and preference points (veterans, pre-apprenticeship graduates) are set by each training committee — ask your local for its selection procedure.
Retake policies are set by each local, not by GAN HR. Common waiting periods run from 90 days to a year, or the next application cycle. If you fall short, ask about the retest policy the same day, diagnose which sections cost you, and start targeted practice immediately. Coming back with a visibly stronger score is a story interview panels respect.
Each trade hub on this site carries a free practice test built in the GAN format — timed sections, no calculator, instant scoring. Start with the one for your trade:
Then drill by section:
The full technique breakdown, a 4-week plan, and a test-day checklist live in the GAN aptitude test study guide. PipePrep AI was built by a federally recognized pre-apprenticeship instructor, and everything here reflects how the battery is actually administered — not test-prep folklore.
The material is roughly high-school level — fractions, decimals, percentages, number patterns, careful reading, and basic mechanical intuition. What makes it hard is the format: about 140 questions across six separately timed sections in roughly two hours, with no calculator. Applicants who walk in cold usually run out of time on the math sections. Two to four weeks of daily timed practice is typically enough to move a score meaningfully.
There is no single universal passing score. A common minimum is around 70% (roughly a 4 on a 9-point scaled score), and some pipefitter and steamfitter locals set the bar higher. More importantly, most locals rank applicants — so merely clearing the minimum puts you near the bottom of the list. Aim well above the cutoff, and confirm the qualifying standard with the local you are applying to.
No. The GAN battery does not allow a calculator on any section. All arithmetic — fractions, decimals, percentages, and multi-step word problems — is done by hand on provided scratch paper. This is why fraction and decimal fluency is the single highest-return skill to drill before test day.
No. GAN Human Resources administers a standardized battery for many UA locals (and some other trades’ training programs), but each local chooses its own testing provider, qualifying score, and selection procedure. Some locals use a different exam entirely — for example, Steamfitters Local 638 in New York City uses the Wiesen Test of Mechanical Aptitude. Your invitation letter describes YOUR test; always verify with your local.
Structured preparation is worth it — the test rewards fluency under time pressure, which only comes from practice. Whether you use a paid guide or free resources matters less than doing timed, section-specific practice. Start with our free study guide and the free practice tests on this site, then add drilling wherever your scores are weakest.
Scores feed the local’s ranked eligibility list, and those lists commonly last one to two years before a new application cycle starts. If the list expires before your number comes up, you reapply and retest. Ask your local how long its list stays active — policies vary.
Results typically come back within about 60 days, delivered through the training center rather than directly from the testing session. Some locals move faster. Use the waiting period to prepare for the oral interview — it usually counts toward your rank alongside the test.
You can usually retest, but the waiting period is set by each local — commonly anywhere from 90 days to a year, or the next application cycle. Ask about the retest policy right away, then use the wait for targeted practice on the sections that hurt you. Plenty of current journeymen needed a second attempt.
Work backwards. The paper is folded, punched, then you pick the fully unfolded pattern. Reverse each fold one at a time, mirroring the punch across the fold line at every step. Holes multiply with layers — a punch through two layers unfolds into two holes reflected across the crease. Practicing even a dozen problems with real paper builds the mental habit fast.
Weighting is set by each training committee, not published nationally. The math-heavy sections carry the most questions (computation plus problem solving alone are 63 of about 140), so arithmetic fluency has the biggest impact on most composite scores. Ask your local whether it uses a composite or per-section minimums — then prepare for every section anyway.