- What ATT2 Actually Covers
- Prerequisites and Registration Mechanics
- Written and Performance Exam Format
- Walking Through the Ten Standards
- What "Passing" Actually Requires
- A Domain-Sequenced Study Timeline
- Calculator, References, and Open-Book Nuances
- Cost and Fee Structures to Expect
- Who Hires ATT2-Certified Technicians
- Recertification and the Five-Year Clock
- FAQ
- ATT2 requires a current ACI Aggregate Testing Technician - Level 1 credential before you can even sit the exam.
- The written exam is open-book, two hours, ~100 questions, 8-12 per standard across ten domains.
- You need 60% minimum on every individual standard and 70% overall to pass the written portion.
- Three domains - LA abrasion small-size, soundness, and large-size LA abrasion - appear only on the written exam, not the performance exam.
What ATT2 Actually Covers
Aggregate Testing Technician - Level 2 (ATT2) is an American Concrete Institute (ACI) certification built on top of the Level 1 credential. It verifies that a technician can run and interpret the more advanced aggregate physical property tests used in concrete mix design, quality control, and materials acceptance testing. If you're just getting oriented, our companion pieces on what ATT2 is and what the ATT2 designation means cover the basics; this guide is focused entirely on how to actually pass it.
The certification's content is defined by ACI's Job-Task Analysis for ATT2, approved September 30, 2024, and its administrative rules live in CPP 620.3-20 (revised September 21, 2020). Every question on the written exam and every task on the performance exam traces back to one of the ten domains listed below - there is no filler content and no surprise material outside those standards.
Prerequisites and Registration Mechanics
Before you can register for ATT2, you must hold a current ACI Aggregate Testing Technician - Level 1 certification. There's no way around this - it's a hard prerequisite baked into CPP 620.3-20, not a suggestion. If your Level 1 credential has lapsed, resolve that first. For a full breakdown of eligibility rules, see ATT2 requirements and eligibility.
Because ACI certifies through approved sponsoring groups (state ready-mix associations, ACI chapters, and similar organizations) rather than a single testing vendor, registration steps, exam dates, and even fee structures differ by sponsor. Check ATT2 exam dates and testing windows before assuming a national calendar exists - it doesn't.
Written and Performance Exam Format
ATT2 certification requires passing two distinct components:
- Written examination: Open-book, using only ACI-approved references, two hours long, approximately 100 multiple-choice questions. Each of the ten standards contributes eight to 12 questions.
- Performance examination: Closed-book. You must correctly demonstrate - or, where permitted, verbally describe - the prescribed procedure steps for the practical standards.
Not every standard shows up on the performance exam. AASHTO T 96/ASTM C131 (LA abrasion, small-size coarse aggregate), AASHTO T 104/ASTM C88 (soundness), and ASTM C535 (LA abrasion, large-size coarse aggregate) are written-examination-only. That leaves seven standards as practical, hands-on performance areas. This split matters for how you allocate study time - memorize procedural sequence and terminology hard for those three, but budget hands-on practice time for the other seven.
Key Takeaway
Because the written exam is open-book, your prep should emphasize knowing where each figure lives in your approved references and being fast at using them - not blind memorization of every number.
Walking Through the Ten Standards
Each domain below corresponds to one of the standards tested on both exam components (except where noted as written-only). For a deeper dive into each area, see our full ATT2 exam domains guide.
Domain 1: AASHTO T 19/ASTM C29/C29M - Bulk Density and Voids
Covers rodding, jigging, and shoveling procedures for determining unit weight, plus the void calculation using bulk density and specific gravity.
- Know when each compaction method (rod, jig, shovel) applies based on aggregate size
Domain 2: AASHTO T 96/ASTM C131 - LA Abrasion, Small-Size Coarse Aggregate
Written-exam-only. Focuses on grading requirements, charge selection, and percent loss calculation after machine revolutions.
- Memorize grading-to-charge relationships since there's no hands-on demo
Domain 3: AASHTO T 104/ASTM C88 - Soundness by Sodium/Magnesium Sulfate
Written-exam-only. Covers cycle counts, solution preparation, and evaluating weighted percentage loss.
- Distinguish sodium sulfate vs. magnesium sulfate solution specifics
Domain 4: AASHTO T 112/ASTM C142 - Clay Lumps and Friable Particles
Sample preparation, wet-sieving technique, and the friable particle identification process.
- Practice distinguishing friable particles from durable ones by hand pressure
Domain 5: AASHTO T 113/ASTM C123 - Lightweight Pieces
Heavy-liquid float/sink separation procedure and percentage calculation of lightweight material.
- Know the specific gravity liquid setup and safety handling steps
Domain 6: AASHTO T 176/ASTM D2419 - Sand Equivalent Test
Plastic fines evaluation in graded aggregates and soils; agitation, sedimentation, and reading clay/sand column heights.
- Drill the timing sequence - sedimentation time errors are a common failure point
Domain 7: AASHTO T 304/ASTM C1252 - Uncompacted Void Content, Fine Aggregate
Method A/B/C selection based on grading, funnel-and-cylinder procedure, and void content calculation.
- Practice consistent funnel-fill technique to avoid segregation errors
Domain 8: ASTM C535 - LA Abrasion, Large-Size Coarse Aggregate
Written-exam-only. Same abrasion-machine principle as Domain 2 but scaled for larger aggregate and different charge/grading tables.
- Compare charge tables side-by-side with Domain 2 to avoid mixing up the two
Domain 9: ASTM D4791 - Flat, Elongated, or Flat and Elongated Particles
Proportional caliper device use, ratio measurement, and particle classification.
- Get hands-on time with the proportional caliper - it's a performance-exam skill
Domain 10: ASTM D5821 - Percentage of Fractured Particles
Visual criteria for counting fractured faces and calculating percentage by particle count or mass.
- Practice visual judgment calls on borderline fractured vs. rounded particles
What "Passing" Actually Requires
ATT2 has one of the stricter scoring structures among ACI aggregate credentials: you must score at least 60% on every single standard and at least 70% overall on the written exam. Scoring 90% overall but 50% on one standard still means a fail. This is different from a simple overall-percentage cutoff, and it changes how you should study - you cannot coast on strong domains to cover weak ones.
The performance examination is graded separately and must also be passed, with correct demonstration (or, where permitted, verbal description) of each prescribed step. For the complete scoring breakdown, read exactly what score you need to pass ATT2.
| Component | Format | Length/Volume | Passing Standard |
|---|---|---|---|
| Written Exam | Open-book (ACI-approved references) | 2 hours, ~100 MCQs, 8-12 per standard | 60% per standard, 70% overall |
| Performance Exam | Closed-book | 7 practical standard areas | Correct demonstration/verbal description of steps |
A Domain-Sequenced Study Timeline
Rather than a generic weekly planner, sequence your study around exam-format logic: tackle the written-only domains early since they require pure recall, then move into the seven practical domains where hands-on repetition matters more than reading time.
Written-Only Standards
- Master Domain 2 (T 96/C131), Domain 3 (T 104/C88), and Domain 8 (C535) - no performance demo needed, so front-load the memorization
- Build a comparison chart for the two LA abrasion standards (small vs. large aggregate) to avoid confusing charge tables
Density, Voids, and Particle Shape
- Work Domain 1 (T 19/C29) rodding/jigging/shoveling methods hands-on
- Practice the proportional caliper for Domain 9 (D4791) until measurements are consistent
Contamination and Composition Tests
- Run Domain 4 (T 112/C142) clay lumps procedure and Domain 5 (T 113/C123) lightweight pieces separation
- Time yourself on Domain 6 (T 176/D2419) sand equivalent sedimentation steps
Fine-Aggregate Voids and Fracture Judgment
- Drill Domain 7 (T 304/C1252) funnel-cylinder technique across methods A/B/C
- Practice Domain 10 (D5821) fractured-particle visual calls with a study partner for calibration
- Run a full open-book practice set against your ACI-approved references to check timing
If you want a deeper explanation of why the domains carry different question weights and what "hard" actually means for this exam, see how hard the ATT2 exam really is and the broader ATT2 study guide.
Calculator, References, and Open-Book Nuances
A simple-function, nonprogrammable pocket calculator is permitted on the written exam - leave anything programmable or graphing at home; it's a disqualification risk, not a convenience. Because the written exam is open-book with ACI-approved references, your prep time is better spent building fast lookup habits (tabbed sections, highlighted tables) than trying to memorize every constant in AASHTO T 19 or ASTM D4791.
ACI's official preparation workbook is CP-45, seventh edition. It's the resource most sponsoring groups build their review sessions around, and it maps directly onto the ten domains covered above. Some chapter packages (see cost section) bundle it into registration; others require you to purchase it separately.
Key Takeaway
Tab your CP-45 workbook by domain before exam day - the open-book format only helps if you can find the right page in under 30 seconds per question.
Cost and Fee Structures to Expect
There is no single national ACI fee for ATT2 - pricing is set by the sponsoring chapter or association running your session. Two published 2026 examples illustrate the range:
- ACI Intermountain Chapter (Utah): USD 500 for chapter members or USD 600 for nonmembers, which includes the study guide, review session, written exam, and performance exam.
- CRMCA (Denver, at CDOT headquarters): USD 598 for members or USD 928 for nonmembers for the full examination, with workbooks purchased separately, no exam-day training or review included, and a 3.05% credit-card processing fee.
If you only need the standalone CP-45 seventh-edition workbook without a bundled course, ACI sells it directly for USD 133 regular price or USD 69 for ACI members. For a full pricing comparison across sponsoring groups, see ATT2 certification cost breakdown.
Who Hires ATT2-Certified Technicians
ATT2 certification signals to employers that a technician can independently run advanced aggregate physical property testing beyond entry-level unit weight and moisture checks. Typical hiring contexts include ready-mix concrete producers, aggregate quarries and processing operations, materials testing laboratories, and departments of transportation materials divisions that require certified staff for acceptance testing on public projects. To explore practical career paths and where postings typically appear, see ATT2 jobs and our analysis of whether ATT2 certification is worth it.
Because ATT2 builds directly on Level 1 and adds specialized tests like sand equivalent, LA abrasion (both size classes), soundness, and particle shape/fracture analysis, it's often the credential DOT specs or producer QC programs point to when a Level 1 technician is ready to take on lab-lead or QC-technician responsibilities.
Recertification and the Five-Year Clock
ATT2 certification is valid for five years. Recertification isn't a paperwork renewal - it requires passing both the written and performance examinations again in full. Treat your five-year window as a planning horizon: keep your CP-45 workbook and notes rather than discarding them after your first pass, since you'll need to relearn the same ten domains eventually.
If you're weighing whether the investment holds up over that five-year cycle, our ATT2 salary guide looks at earnings context, and you can run full-length ATT2 practice tests at any point in your recertification cycle to gauge readiness before you commit to a session date.
FAQ
ACI doesn't mandate a specific training course, but you must already hold a current Aggregate Testing Technician - Level 1 certification. Many candidates combine self-study from the CP-45 workbook with a sponsoring chapter's review session. See ATT2 training options for more detail.
AASHTO T 96/ASTM C131 (LA abrasion, small-size coarse aggregate), AASHTO T 104/ASTM C88 (soundness), and ASTM C535 (LA abrasion, large-size coarse aggregate) are tested only on the written exam.
You keep the passed written result and only need to retake the performance exam, provided you do so within one year of your written pass. After one year, a failed or expired component must be retaken in full.
Each standard contributes roughly 8 to 12 questions, and you need at least 60% correct on every individual standard plus 70% overall - so no single domain can be safely skipped, regardless of perceived difficulty.
No. ACI certifies through approved sponsoring groups, and published 2026 examples show real variation - from USD 500-600 for a bundled Utah chapter package to USD 598-928 for Colorado's CRMCA program with workbooks purchased separately. Check your specific sponsoring group's fee sheet before budgeting.