ATT2 Exam Domains 2026: Complete Guide to All 10 Content Areas

Why the Ten ATT2 Domains Structure the Entire Exam

Every question on the ATT2 written exam and every task on the performance exam maps back to one of ten specific aggregate testing standards. Unlike certifications that spread questions loosely across broad topics, ACI's Aggregate Testing Technician - Level 2 program builds its two-hour, roughly 100-question written exam around a fixed structure: eight to 12 questions from each of the ten standards below. That means no domain can be skipped, and no domain can be over-relied on to compensate for weakness elsewhere, because you must clear 60% on every individual standard in addition to 70% overall.

If you're building a study plan, this domain structure is the single most useful piece of information you can work from. Instead of guessing what to review, you can allocate time in direct proportion to how the exam is actually built. For a step-by-step study framework built on top of this same domain map, see the ATT2 Study Guide 2026.

Where the Domains Come From: The 2024 Job-Task Analysis

The ten domains aren't arbitrary. They come directly from ACI's Aggregate Testing Technician - Level 2 Job-Task Analysis (JTA), approved September 30, 2024. The JTA defines what a working ATT2 technician actually does in the field and lab, and ACI builds exam content specifications directly from it. Administration rules, scoring thresholds, and retake policies are separately codified in CPP 620.3-20, revised September 21, 2020, which functions as the governing policy document for the whole certification.

In practice, this means the exam content is tied to real job tasks: running Los Angeles Machine abrasion tests, sizing and weighing clay lumps, running sand equivalent tests on graded aggregate, and reporting bulk density and voids calculations correctly. Employers hiring for aggregate testing roles - materials labs, ready-mix producers, DOT testing programs, and geotechnical firms - expect ATT2 holders to be fluent in all ten, not just the ones that show up most often on a given exam form.

The Ten ATT2 Study Domains at a Glance

Here is the complete list of standards covered on the ATT2 written and performance exams, in the order ACI presents them in its JTA and study materials.

Domain-by-Domain Breakdown

Written-Only vs. Practical Domains

Of the ten domains, three are tested exclusively on the written exam: AASHTO T 96/ASTM C131, AASHTO T 104/ASTM C88, and ASTM C535. That leaves seven domains - bulk density, clay lumps, lightweight pieces, sand equivalent, uncompacted voids, flat and elongated particles, and fractured particles - as the practical standards you'll need to demonstrate on the closed-book performance exam.

The performance exam requires you to correctly demonstrate, or in some cases verbally describe, the prescribed procedure steps for each of those seven standards. Because it's closed-book, memorized sequencing matters far more here than on the written exam, where ACI-approved references are permitted. If you're trying to gauge how much this practical component adds to overall exam difficulty, the How Hard Is the ATT2 Exam guide breaks down the written and performance components separately.

Scheduling the Ten Domains Into a Study Plan

Because the exam weights every domain almost equally (eight to 12 questions each), a sensible plan spreads study time across all ten rather than over-investing in one or two. A domain-anchored schedule also makes it easier to interleave written-only theory with performance-exam procedure practice.

For candidates who want this same domain-by-domain structure paired with practice questions in the exact 8-12-per-standard format used on exam day, the practice sets at ATT2 Exam Prep are built around this breakdown rather than generic aggregate testing trivia.

Registration, Fees, and Timing Logistics

ATT2 exams are administered locally through ACI-approved sponsoring groups rather than through a single national testing center, so pricing and package inclusions vary by chapter. As published examples for 2026: the ACI Intermountain Chapter in Utah lists USD 500 for chapter members and USD 600 for nonmembers, covering the study guide, review session, written exam, and performance exam. CRMCA's program at CDOT headquarters in Denver lists USD 598 for members and USD 928 for nonmembers for the full exam, with workbooks purchased separately, no included exam-day training, and a 3.05% credit-card processing fee. These are local package prices, not a single national ACI fee - always confirm what's included with your specific sponsoring group. A full cost comparison lives in the ATT2 Certification Cost breakdown.

The standalone CP-45 seventh-edition workbook, which ACI uses as the primary preparation reference for all ten domains, costs USD 133 at the regular rate or USD 69 for ACI members if purchased separately from a local package.

On timing: both the written and performance exams must be passed within one year of each other. If you pass one component and fail the other, the passed component stays valid for that one-year window while you retake only the failed one - but a failed component must be retaken in full, not partially. Certification itself lasts five years, after which recertification requires passing both the written and performance exams again. See the ATT2 Exam Dates guide for scheduling specifics and the ATT2 Passing Score guide for the exact 60%/70% scoring rules referenced above.

If you're still weighing whether the credential fits your career path before committing to a sponsoring group and workbook purchase, the Is ATT2 Certification Worth It analysis and the ATT2 Salary Guide are useful starting points, and the practice test platform lets you sample domain-specific questions before you register.

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