ACI-AGGREGATE-L1 Pass Rate 2026: What the Data Shows

Why There's No Official Pass Rate Number

If you're searching for a percentage - "X% of candidates pass ACI-AGGREGATE-L1 on the first try" - you won't find one from the American Concrete Institute. ACI does not publish pass-rate statistics for the Aggregate Testing Technician-Level 1 program the way some other certifying bodies do for their exams. Testing is delivered locally through approved sponsoring groups and ACI examiners or proctors, with ACI handling the grading centrally, but no aggregated national pass-rate figure is released publicly for this specific credential.

That absence of a headline number is actually useful information in itself. Instead of chasing a statistic that doesn't exist, the smarter approach is to study the mechanics that determine whether an individual candidate passes or fails - the scoring thresholds, the two-component structure, and the retest window. Those rules are documented, and they tell you far more about your odds than a vague industry-wide percentage ever could. For a broader look at how tough the exam feels in practice, see How Hard Is the ACI-AGGREGATE-L1 Exam? Complete Difficulty Guide 2026.

The Scoring Mechanics That Actually Decide Pass/Fail

The written examination for Aggregate Testing Technician-Level 1 is open-book, using ACI-approved references, runs on a two-hour limit, and contains approximately 100 multiple-choice questions. What makes the scoring rule distinctive - and what candidates most often misunderstand - is that it isn't a single overall cutoff.

• Per-standard minimum: You need at least 60% correct on each individual required standard tested.
• Overall minimum: You also need at least 70% correct across the entire written exam.

This double-threshold structure means you can't compensate for a weak domain by acing another one. If you score high on sieve analysis questions but bomb the organic-impurities questions and fall under 60% on that standard, you fail the written exam even if your overall percentage clears 70%. This is the single biggest reason candidates who "study generally" underperform compared to candidates who study standard-by-standard. The exact breakdown of every tested standard is covered in ACI-AGGREGATE-L1 Exam Domains 2026: Complete Guide to All 8 Content Areas, and the passing thresholds themselves are broken down further in ACI-AGGREGATE-L1 Passing Score 2026: Exactly What You Need to Pass.

Two Components, Two Separate Ways to Fail

Aggregate Testing Technician-Level 1 certification isn't earned through the written test alone. A separate closed-book performance examination is also required, and it demands successful completion of every required procedure - with verbal descriptions permitted only where the standard allows it. There's no partial credit system here comparable to the written exam's percentages; each procedural step either meets the required method or it doesn't.

This means candidates face two fundamentally different failure modes:

Because both must be passed within one year of each other, a candidate who passes the written exam but struggles with lab technique on the performance side is racing a clock. And a retest, when needed, covers the entire failed component - not just the specific procedure or question set you missed. That's a meaningful planning detail worth internalizing before you schedule your first attempt; see ACI-AGGREGATE-L1 Requirements 2026: Eligibility, Prerequisites & How to Qualify for how the two components fit into overall eligibility.

Domain-by-Domain: Where Candidates Lose Points

The eight domains for Aggregate Testing Technician-Level 1 are the official paired AASHTO/ASTM standard areas, not loosely-themed topic buckets. Each one corresponds to a specific test method you'll need to know cold, both for the multiple-choice questions and for the hands-on performance procedures.

Because the written exam applies its 60% floor to each standard individually, a candidate can't afford to treat any one of these eight domains as an afterthought. A deeper walkthrough of study priorities for each is in ACI-AGGREGATE-L1 Study Guide 2026: How to Pass on Your First Attempt.

Retest Rules and the One-Year Clock

Both the written and performance components must be passed within one year of each other. If that window closes without both passes recorded, you're back to square one on whichever piece remains incomplete - or potentially both, depending on timing.

When a retest is needed, it covers the entire failed component, not a subset of missed questions or procedures. Eligible written retests can be taken through Prometric in addition to sponsor-administered sessions, which gives some scheduling flexibility if your local sponsor's next session is far off. Fee-wise, this matters practically: a written retest and a performance retest are typically priced differently from a full initial certification attempt at the sponsor level, so knowing which component you need to redo affects your budget. For a full pricing breakdown including sponsor-level examples, see ACI-AGGREGATE-L1 Certification Cost 2026: Complete Pricing Breakdown, and for scheduling logistics see ACI-AGGREGATE-L1 Exam Dates 2026: Testing Windows, Deadlines & Scheduling.

What the Open-Book Format Tells You About Difficulty

An open-book written exam sounds forgiving, but in practice it changes the nature of difficulty rather than removing it. With approximately 100 multiple-choice questions and a two-hour limit, you don't have time to look up every answer from scratch - you need to already know roughly where each standard's key figures live (tolerances, minimum sample sizes, timing requirements) and use your ACI-approved references only to confirm or calculate, not to learn the material cold during the test.

This is a meaningful distinction from exams that are purely closed-book recall or purely open-note. It rewards candidates who've built genuine procedural fluency across all eight domains and who know their reference documents well enough to navigate them quickly under time pressure. Practicing with realistic multiple-choice questions ahead of time - through resources like a dedicated practice test platform - helps you get faster at that navigation before test day, rather than discovering the time crunch for the first time when it counts.

A Domain-Ordered Study Timeline

Generic study techniques only matter when they're mapped onto the actual eight domains and the two-component structure described above. Here's one way to sequence preparation so the heaviest calculation domains get the most runway.

Note that sample gravity and moisture-content domains involve real math under time pressure - this is where the two-hour written limit bites hardest, so save extra practice time for Domains 4 through 7. For more structured pacing advice, ACI-AGGREGATE-L1 Study Guide 2026: How to Pass on Your First Attempt goes deeper into week-by-week planning.

Who Actually Sits This Exam

Candidates for Aggregate Testing Technician-Level 1 typically work in or around materials testing labs, construction quality control, aggregate producers, and transportation agencies that require ACI-recognized aggregate testing credentials on project documentation. There are no specific education or work-experience prerequisites to sit the exam, which means the candidate pool ranges from newer lab technicians building their first credential to experienced field staff formalizing skills they've already practiced informally.

Because certification lasts five years and renewal requires passing both the written and performance examinations again, this isn't a one-time checkbox - it's a credential employers expect to see refreshed periodically. That renewal structure is worth factoring into whether the certification is worth pursuing for your career path; see Is the ACI-AGGREGATE-L1 Certification Worth It? Complete ROI Analysis 2026 and ACI-AGGREGATE-L1 Jobs for more on where this credential shows up in job postings.

If you want a broader run-up on what this certification actually covers before diving into domain-level prep, start with What Is ACI-AGGREGATE-L1 Certification? or browse practice questions on the main practice test site to see how the multiple-choice format feels before exam day.

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