- ATT2 means Aggregate Testing Technician - Level 2, an ACI credential requiring a current Level 1 certification first.
- The written exam is open-book, two hours, ~100 questions covering ten standards, eight to 12 per standard.
- You need 60% minimum per standard, 70% overall, plus a passed performance exam, both within one year.
- Three standards (T 96/C131, T 104/C88, C535) are written-only; seven others also require hands-on demonstration.
What ATT2 Actually Stands For
ATT2 stands for Aggregate Testing Technician - Level 2, a certification developed and administered under the American Concrete Institute (ACI) framework. It is important to be precise here: several unrelated credentials in other industries also use the abbreviation "ATT2," but on this site, and in every article linked below, ATT2 refers exclusively to the aggregate-testing credential described in ACI's Job-Task Analysis and certification policy documents. If you searched for ATT2 and landed somewhere with a different fee schedule, different domains, or a different governing body, you were reading about a different program entirely.
For a broader orientation to the credential before diving into mechanics, see What Is ATT2? and ATT2 Meaning, both of which unpack the acronym in more depth than a single definition can.
Who Issues the ATT2 Credential
Examinations for Aggregate Testing Technician - Level 2 are administered through ACI-approved sponsoring groups and examiners, not through a single national testing center. This is a meaningful detail: the entity that trains you, collects your fee, and proctors your exam is typically a regional chapter, a ready-mix concrete association, or a similar sponsoring organization operating under ACI's rules - not ACI headquarters directly. That structure explains why fees, class schedules, and even review sessions vary by location, even though the exam content and passing standards themselves are fixed by ACI policy documents.
The governing rules for how the exam is built and scored are laid out in CPP 620.3-20 (revised September 21, 2020), and the content itself follows ACI's Job-Task Analysis approved September 30, 2024. If a training provider or study resource references domains, weights, or a passing structure that doesn't match those documents, treat it with caution - it's likely describing a different "ATT2."
Prerequisites You Cannot Skip
Certification requires a current ACI Aggregate Testing Technician - Level 1 credential. This is not a suggestion or a "recommended background" - it's a hard eligibility gate. If your Level 1 has lapsed, you need to resolve that before a sponsoring group will even let you register for Level 2 testing.
For the full breakdown of what "current" means, how long Level 1 stays valid, and what documentation sponsoring groups typically ask for, see ATT2 Requirements 2026: Eligibility, Prerequisites & How to Qualify.
How the ATT2 Exam Is Structured
ATT2 certification has two distinct components, and you must pass both:
- Written examination: Open-book, using ACI-approved references only. It runs two hours and contains approximately 100 multiple-choice questions, with eight to 12 questions drawn from each of the ten standards listed below.
- Performance examination: Closed-book. You must correctly demonstrate - or, where permitted, verbally describe - the prescribed procedure steps for the practical standards.
A simple-function, nonprogrammable pocket calculator is permitted during testing. Because the written exam is open-book, memorization matters less than knowing exactly where each procedure, tolerance, and formula lives in your approved references and being fast enough to find it under time pressure.
Key Takeaway
Open-book does not mean easy. With roughly 100 questions in two hours across ten standards, you have just over a minute per question on average - you need a tabbed, organized reference set walked through in advance, not a cold search during the exam.
The Ten Standards ATT2 Covers
The ATT2 Job-Task Analysis organizes content into ten standards. Three of them - AASHTO T 96/ASTM C131, AASHTO T 104/ASTM C88, and ASTM C535 - are written-examination-only, meaning you won't be asked to physically demonstrate them, but you are still tested on them in the multiple-choice portion. The remaining seven appear on both the written and performance exams.
Domain 1: AASHTO T 19/ASTM C29/C29M - Bulk Density ("Unit Weight") and Voids in Aggregate
Candidates must understand how to determine bulk density using shoveling, rodding, or jigging procedures depending on aggregate size, plus how to calculate percentage of voids.
- Know which compaction method applies to which aggregate size
- Practice the voids calculation formula until it's automatic
Domain 2: AASHTO T 96/ASTM C131 - Resistance to Degradation by Abrasion and Impact (L.A. Machine, Small-Size Coarse Aggregate)
Written-only. Focus on grading requirements, charge selection, and how abrasion loss is calculated and reported.
- Match aggregate grading to the correct steel ball charge
Domain 3: AASHTO T 104/ASTM C88 - Soundness of Aggregate (Sodium or Magnesium Sulfate)
Written-only. Understand the cyclical immersion-and-drying process and how weighted percentage loss is used to judge soundness.
- Know the difference between sodium sulfate and magnesium sulfate result interpretation
Domain 4: AASHTO T 112/ASTM C142 - Clay Lumps and Friable Particles in Aggregate
Requires understanding the wet-sieving and breakdown procedure used to isolate and quantify clay lumps and friable particles.
- Be ready to demonstrate the gentle finger-pressure breakdown technique
Domain 5: AASHTO T 113/ASTM C123 - Lightweight Pieces in Aggregate
Covers the heavy-liquid flotation method used to separate and quantify lightweight particles.
- Know the correct liquid density ranges used for separation
Domain 6: AASHTO T 176/ASTM D2419 - Sand Equivalent Test
One of the more procedure-heavy practical domains: irrigation, agitation, settling time, and reading clay and sand column heights.
- Memorize the required settling time before readings are taken
Domain 7: AASHTO T 304/ASTM C1252 - Uncompacted Void Content of Fine Aggregate
Tests understanding of the flow-through-funnel method and void content calculation for fine aggregate.
- Practice consistent funnel-filling technique to avoid compaction bias
Domain 8: ASTM C535 - Resistance to Degradation of Large-Size Coarse Aggregate
Written-only. The large-aggregate counterpart to Domain 2, with different charge and revolution requirements.
- Don't confuse C535 charge specs with T 96/C131 charge specs
Domain 9: ASTM D4791 - Flat, Elongated, or Flat and Elongated Particles in Coarse Aggregate
Focuses on using a proportional caliper device correctly and applying the specified ratio criteria.
- Be precise about which dimension ratio defines "flat and elongated" versus just "flat" or "elongated"
Domain 10: ASTM D5821 - Percentage of Fractured Particles in Coarse Aggregate
Requires visual classification judgment: distinguishing fractured faces from rounded or natural surfaces per the standard's fraction-of-face rule.
- Practice edge cases where a particle has a fracture covering close to the minimum required area
For a deeper walkthrough of how these ten domains interact with question weighting and study sequencing, see ATT2 Exam Domains 2026: Complete Guide to All 10 Content Areas.
What ATT2 Costs in Practice
There is no single national ACI price for the ATT2 exam - cost depends entirely on which sponsoring group administers your session, because fees are set locally and packages vary in what they include.
| Provider (2026) | Member Price | Nonmember Price | What's Included |
|---|---|---|---|
| ACI Intermountain Chapter (Utah) | USD 500 | USD 600 | Study guide, review session, written exam, performance exam |
| CRMCA (Denver, CDOT HQ) | USD 598 | USD 928 | Written and performance exam only; workbooks separate; no exam-day training; 3.05% card-processing fee applies |
| ACI CP-45 workbook (standalone) | USD 69 (member) | USD 133 (regular) | Seventh-edition preparation workbook only |
These two examples show why comparing "ATT2 cost" across sources without checking what's bundled can be misleading - one package includes a review class and study guide, the other charges separately for workbooks and adds a card-processing surcharge. For a fuller pricing breakdown across providers, read ATT2 Certification Cost 2026: Complete Pricing Breakdown.
Validity Period and Recertification
ATT2 certification lasts five years. Recertification requires passing both the written and performance examinations again - there is no abbreviated renewal path. Within your initial certification attempt, both components must be passed within a one-year window of each other: if you pass the written exam but fail the performance exam, you retain the passed written score for that year while retaking only the performance portion. A failed component, on the other hand, must be retaken in full - there's no partial credit or question-by-question retry.
For exact passing thresholds and how scores are calculated per standard, see ATT2 Passing Score 2026: Exactly What You Need to Pass. For scheduling windows and how sponsoring groups typically run sessions throughout the year, check ATT2 Exam Dates 2026: Testing Windows, Deadlines & Scheduling.
Who Actually Needs ATT2
ATT2 is aimed at technicians already working with aggregate testing in materials labs, aggregate quarries, ready-mix concrete plants, DOT testing programs, and construction materials testing firms who need to move beyond entry-level Level 1 responsibilities. Because the credential builds directly on Level 1 and adds procedural depth across ten standards, employers use it as evidence that a technician can independently run and interpret a broader set of aggregate quality tests - not just perform basic sampling and simple density checks.
If you're weighing whether pursuing ATT2 makes sense for your career path or current role, Is the ATT2 Certification Worth It? Complete ROI Analysis 2026 and ATT2 Jobs go into more detail on employer expectations and typical job postings that reference the credential.
Mapping Study Time to the Standards
Because the written exam allocates eight to 12 questions to each of ten standards, uneven study time is a common mistake - spending three weeks on one favorite domain and two days on another leaves gaps that show up in the 60%-per-standard requirement. A more balanced approach treats each standard as roughly equal in exam weight, then adjusts slightly for procedural complexity.
Written-Only Standards
- Master T 96/C131, T 104/C88, and C535 first since they're tested only in multiple-choice format - no procedure rehearsal needed, just calculation and specification recall
Calculation-Heavy Practical Domains
- Work through T 19/C29 (unit weight and voids) and T 304/C1252 (uncompacted void content), practicing the math until it's second nature
Procedure-Heavy Practical Domains
- Rehearse T 112/C142, T 113/C123, and T 176/D2419 hands-on, since these rely on multi-step wet procedures that are easy to fumble under performance-exam pressure
Visual Classification Domains
- Drill D4791 and D5821 using sample particle sets, since these require judgment calls rather than formulas
Full Review and Timed Practice
- Run full-length timed question sets and a mock performance walkthrough covering all seven practical standards
This kind of standard-by-standard scheduling is more effective than generic study techniques applied blindly, because ATT2's scoring structure rewards even coverage across all ten domains rather than depth in just a few. For a structured week-by-week plan built specifically around this exam, see ATT2 Study Guide 2026: How to Pass on Your First Attempt, and for an honest assessment of where candidates typically struggle, read How Hard Is the ATT2 Exam? Complete Difficulty Guide 2026.
Once you've got a study rhythm going, a condensed one-page reference of key figures, calculation formulas, and standard-specific tolerances can help during final review. See ATT2 Cheat Sheet 2026: One-Page Review of Must-Know Facts for a compact version of the material covered above.
Frequently Asked Questions
In the context of aggregate and construction materials testing, ATT2 refers specifically to Aggregate Testing Technician - Level 2, an ACI credential. Other industries may use the same acronym for unrelated programs, but those have different requirements, fees, and governing bodies entirely.
No. A current ACI Aggregate Testing Technician - Level 1 credential is a prerequisite for ATT2 certification. Sponsoring groups verify this before allowing registration.
Yes, it's approximately 100 multiple-choice questions across a two-hour period, and it's open-book using ACI-approved references. A simple-function, nonprogrammable pocket calculator is also permitted.
You keep your passed written score and only need to retake the performance exam, as long as you complete both components within one year. A failed component must be retaken in full.
Five years. Recertification requires passing both the written and performance examinations again in full - there is no shortened renewal process.
For a broader look at what the credential involves beyond definitions and fees, explore ATT2 Certification, What Is ATT2 Certification?, and ATT2 Training. If you're still deciding how to prepare, our practice test platform offers domain-tagged questions matching the ten standards described above.