10.2 Category Scoring and the No-Compensation Rule

Two Independent Passing Requirements

The most important scoring fact on the Grade I written exam is that there are two passing requirements working together. To pass you need at least 60% correct in each required test method or practice and at least 70% correct overall. Neither requirement rescues the other. A strong total cannot erase a failed method category, and acing every individual method does not help if the overall total stays below 70%.

The exam has 55 questions. Seventy percent of 55 is 38.5, so you need at least 39 correct answers overall — and the rounding direction matters, because 38 is a fail. But 39 correct is not automatically a pass. If your misses cluster in one standard, you can still fail under the per-method minimum even with a comfortable total. This is the no-compensation rule: categories are scored independently.

Why does ACI structure scoring this way? A field technician who is excellent at slump but unreliable at sampling would generate bad data on real projects, because every downstream test depends on a representative sample. The dual rule forces broad competence rather than a single strength. It mirrors the job: you cannot be allowed to skip the standard you dislike, so the exam will not let a brilliant slump score paper over a sampling weakness. Read the rule as a description of the job, not an arbitrary hurdle.

Convert 60% Into Minimum Correct Answers

Because questions are spread 5 to 10 per standard, a percentage minimum becomes a small, brittle count. Memorize the table so you instinctively know how thin the margin is in a small category.

Notice how unforgiving the small categories are. In a 5-question category, two misses already drops you to 3 of 5 — exactly at the line — and a third miss fails it outright. In a 6-question category you must get 4 of 6. You will not always know how many questions a given standard received, so during study assume every method needs a margin above the bare minimum.

Now work two scenarios. A candidate answers 42 of 55 correctly — clearly above 70% overall. But if they get only 2 of 5 sampling questions, the sampling category is at 40%, below 60%, so the written exam is not passed. Reverse it: a candidate clears 60% in every category but totals only 38 of 55. That is 69.1% overall, below 70%, so again the exam is not passed. Both halves of the rule must be satisfied at the same time.

Let the Rule Shape Your Study Plan

The no-compensation rule is actually good news if you use it early: it tells you exactly where risk lives. Do not take ten mixed practice exams and celebrate only the total percent. Break every practice set into the seven standards — C172 sampling, C1064 temperature, C143 slump, C138 density, C231 pressure air, C173 volumetric air, and C31 specimens — and score each separately.

Use this scoring routine after every practice test:

1. Count total correct out of 55 and confirm it is at least 39.
2. Sort each missed question by its ASTM standard.
3. Compute the percent correct for each category.
4. Flag any category below 75% as a risk, even if it cleared 60%.
5. Re-study the exact concepts behind those misses.
6. Retest the weak standard with a small focused set before another full mixed exam.
7. Keep a readiness sheet showing both the total score and every category score.

The weakest method controls your risk because it can fail the exam even when the total looks safe. A candidate who finds and repairs a weak category during practice never has to discover it on the official exam — where there is no second chance within that session.

A worked planning example shows the leverage. Suppose your last three mixed exams averaged 44 of 55 overall — a comfortable 80% — but your sampling category sat at 3 of 5, exactly 60%. The total tempts you to relax, yet sampling is one careless miss from failure. The right move is not another full mixed exam; it is a focused C172 session until sampling reliably scores 4 or 5 of 5. That single repair changes your readiness more than raising an already-safe 80% total to 82%. The dual rule rewards fixing the floor, not raising the ceiling.

Remember too that the overall and per-method requirements are checked on the same attempt. You do not pass the overall portion one day and the categories another; one administration must satisfy both. That is why the readiness sheet pairs the two numbers side by side — you are ready only when the total clears 39 of 55 and every category clears its 60% line at the same time.