- What the Performance Exam Actually Is
- Before You Arrive: Logistics, PPE, and Paperwork
- The Six Hands-On Tests You Will Perform
- C172: The Oral Description Wildcard
- How Examiners Score You
- The Written Component: Same Day, Different Standard
- A Realistic Prep Schedule Tied to the Domains
- Who Hires ACI-Certified Technicians and Why It Matters
- Cost, Funding, and Certification Timeline
- Frequently Asked Questions
- The performance exam requires you to physically demonstrate six ASTM test procedures and orally describe one - closed book, no guides allowed.
- PPE is mandatory: safety-toe shoes, long pants, a sleeved shirt, and safety glasses must be worn or you may not test.
- Scoring is pass/fail on each required step - partial credit is not given for skipping or incorrectly sequencing a procedure.
- The written exam requires at least 60% on each of the seven ASTM sections AND 70% overall to pass - both thresholds must be met simultaneously.
What the Performance Exam Actually Is
Most credentialing exams are multiple-choice tests in a quiet room. The ACI Concrete Field Testing Technician Grade I performance exam is something different: you stand at a concrete truck or mixing station and physically demonstrate that you can execute real ASTM test procedures correctly, in sequence, under observation. It is not a simulation. It is not a worksheet. A trained ACI examiner watches every move you make and marks whether each required step was performed correctly.
The American Concrete Institute - headquartered in Farmington Hills, Michigan - administers this certification exclusively through its network of more than 135 Sponsoring Groups. These are local ACI chapters, concrete industry associations, state transportation agencies, and universities that host exam sessions in their regions. There is no remote option and no computer-based version of the performance component. You must show up in person with your hands ready to work.
Understanding the structure of test day before you get there is one of the highest-leverage investments you can make. This article walks through every component - what you perform, how you are scored, what you must wear, and how the written exam fits alongside the performance component.
Before You Arrive: Logistics, PPE, and Paperwork
Registration Through a Sponsoring Group
You do not register directly with ACI national for the performance exam. You register through a Sponsoring Group in your area. Each group sets its own fee, schedule, and location. Fees typically fall between $450 and $660 or more - for example, ACI Southern California charges $610 for members and $660 for non-members. Some groups host exams seasonally; others run them on demand when enough candidates register. Confirm the specific session format with your Sponsoring Group well in advance, because some groups administer the written and performance components on the same day while others split them across separate dates.
PPE Is Non-Negotiable
ACI requires specific personal protective equipment for the performance exam, and this is not a soft recommendation. You must wear:
- Safety-toe shoes (steel-toe or composite-toe)
- Long pants with no exposed skin below the waist
- A sleeved shirt (short or long sleeve)
- Safety glasses
Arriving without the correct PPE may prevent you from testing. Do not assume a waiver is possible. Buy the safety glasses and the right footwear before the exam date, not the morning of.
What You Are Allowed to Bring
Both the written and performance components are closed book. You may not bring a copy of CP-1, ASTM standards, or any reference sheets. The only tool permitted for the written portion is a simple calculator capable of addition, subtraction, multiplication, division, and square root - no scientific calculator functions, no programmable memory. For the performance component, the equipment is provided at the exam site. You bring your PPE, your knowledge, and nothing else.
The Six Hands-On Tests You Will Perform
The performance exam covers six ASTM procedures that you must physically execute. Each corresponds to a domain in the written exam as well. These are not demonstrations you narrate - you perform them with actual concrete, actual equipment, and an examiner recording every step.
Domain 1: ASTM C1064/C1064M - Temperature of Freshly Mixed Hydraulic-Cement Concrete
You must correctly measure the temperature of fresh concrete using a calibrated thermometer. Key points examiners watch for include proper immersion depth and time, and recording the reading accurately.
- Thermometer must remain immersed for the full required duration
- Correct placement away from aggregate that would skew the reading
- Temperature recorded to the nearest 1°F or 0.5°C
Domain 3: ASTM C143/C143M - Slump of Hydraulic-Cement Concrete
The slump test is one of the most recognizable procedures but also one of the most frequently botched in performance exams because candidates rush the rodding sequence or lift the cone at the wrong rate.
- Three layers, 25 rods per layer, rodding into the layer below on layers two and three
- Cone raised in 5±2 seconds in a smooth, vertical motion - no twisting
- Slump measured to the nearest ¼ inch from the top of the cone to the displaced original center of the specimen
Domain 4: ASTM C138/C138M - Density (Unit Weight), Yield, and Air Content (Gravimetric)
Candidates must consolidate concrete in the measure, strike it off level, and calculate density. Arithmetic errors on the density formula are a common failure point during oral explanation afterward.
- Rodding or vibrating depending on slump range - candidates must know the threshold
- Strike-off must produce a flat, level surface - no crowning or dishing
- Density formula: (mass of concrete) ÷ (volume of measure)
Domain 5: ASTM C231/C231M - Air Content by Pressure Method
The Type B pressure meter is the most equipment-intensive test on the performance exam. Candidates must assemble the meter correctly, pump to the correct pressure, and release - without contaminating the reading.
- Aggregate correction factor must be applied - examiners often ask candidates to explain this step
- Bowl must be struck off properly before attaching the head
- Not valid for lightweight concrete or highly air-entrained mixes with unusual aggregates
Domain 6: ASTM C173/C173M - Air Content by Volumetric Method
The roll-a-meter test is required when the pressure method is not appropriate. Candidates must add the correct amount of isopropyl alcohol, agitate properly, and read the graduated cylinder correctly.
- Used for lightweight aggregate concrete where C231 gives inaccurate results
- Agitation sequence and duration are strictly defined - shortcutting them is a marked failure
- Final reading corrected to account for alcohol added
Domain 7: ASTM C31/C31M - Making and Curing Concrete Test Specimens in the Field
Candidates must make cylinders or beams correctly, demonstrating proper consolidation, rodding depth, finishing, and initial curing placement. This domain is heavily weighted in real-world work.
- Number of layers and rods per layer depends on cylinder size - 4×8 vs. 6×12 differ
- Finish surface must be smooth and flat; capping procedures are part of the knowledge base
- Initial curing temperature range (60°F-80°F) must be maintained for the first 24 hours
C172: The Oral Description Wildcard
ASTM C172/C172M - Sampling Freshly Mixed Concrete - is the one domain where you do not physically take the sample during the performance exam. Instead, you must verbally describe the correct sampling procedure to the examiner. This catches many candidates off guard because it requires precise recall without any physical cue to prompt you.
The key points examiners expect you to cover include: the timing window after discharge begins, the number of portions required to make a composite sample, the total time allowed to complete sampling and start testing, and why samples from the very beginning or very end of the discharge are excluded. Study this procedure with the same rigor you give any physical test - verbal fluency here is just as pass/fail as rodding a cylinder correctly.
How Examiners Score You
Performance exam scoring is pass/fail on a step-by-step basis for each procedure. There is no partial credit structure where performing eight out of ten steps earns you a passing score. If a required step is skipped, performed out of sequence, or executed incorrectly, it is marked as failed for that station. Examiners follow a standardized checklist derived directly from the ASTM standard being tested.
This means the order of operations matters as much as the operations themselves. Striking off the measure before rodding all three layers, or reading the slump before the cone is fully raised, are the kinds of sequencing errors that produce a failing mark even when every individual action looks technically correct in isolation.
Key Takeaway
Practice each test procedure from start to finish without stopping. Real concrete field work often involves shortcuts and improvisation - the performance exam does not. Muscle memory for the exact sequence defined in CP-1 is what passes the exam.
The Written Component: Same Day, Different Standard
The written exam consists of 55 multiple-choice questions delivered in 60 minutes. Questions cover the same seven ASTM domains as the performance exam, with approximately 5-10 questions per test method. The written exam is closed book with no reference materials allowed.
The passing standard has a dual threshold that trips up candidates who don't read the requirements carefully: you must score at least 60% on each of the seven individual ASTM sections AND at least 70% overall. Both conditions must be met simultaneously. Scoring 90% overall but dropping below 60% on, say, the C173 volumetric method section means you have not passed the written exam.
| Exam Component | Format | Time Limit | Passing Standard | Reference Materials |
|---|---|---|---|---|
| Written | 55 multiple-choice questions | 60 minutes | ≥60% per section AND ≥70% overall | None (closed book) |
| Performance | 6 ASTM demonstrations + 1 oral description | Set by examiner/station | Pass/fail per required step | None (closed book) |
Written questions test both conceptual knowledge and applied calculation. You may be asked to calculate slump in inches from raw measurements, compute density using the C138 formula, or identify which test method is appropriate for a lightweight aggregate mix. The ACI Exam Prep practice tests are structured to mirror this format - seven-section scoring so you can see exactly where your section-by-section performance stands before test day.
A Realistic Prep Schedule Tied to the Domains
With seven distinct ASTM domains to master for both recall and physical execution, unfocused studying tends to produce uniform mediocrity across all sections rather than genuine competence in any. A structured approach that sequences domains by difficulty and interdependency works better.
Foundations: C1064 Temperature + C172 Sampling
- Read CP-1 sections for C1064 and C172 back to back - temperature is the first test performed on a fresh sample, and sampling is the prerequisite for everything else
- Memorize the C172 composite sampling sequence and time limits for oral description practice
- Run practice questions on both domains at ACI Exam Prep to identify gaps early
Core Physical Tests: C143 Slump + C138 Density
- These two procedures appear on nearly every field job - practice the physical sequence repeatedly, not just the theory
- Drill the C138 density formula until you can solve it without a prompt
- Focus on rodding layer counts and the strike-off technique for C138
Air Content Methods: C231 Pressure + C173 Volumetric
- Study these two together because a common exam question type asks when to use one versus the other
- Memorize the aggregate correction factor concept for C231
- Practice the C173 agitation sequence - it has the most candidates lose marks due to rushing
Specimen Making + Full Simulation: C31 + Mock Exam
- Master the cylinder and beam consolidation rules for C31, including the 4×8 vs. 6×12 differences
- Run timed full-length practice written exams and check section-by-section scores, not just overall
- Complete one full physical run-through of all six performance procedures in sequence if you have access to equipment
Who Hires ACI-Certified Technicians and Why It Matters
ACI Concrete Field Testing Technician Grade I certification is a standard hiring requirement across a wide range of construction and materials testing roles. State departments of transportation routinely require it for inspectors overseeing concrete pours on publicly funded infrastructure projects. Independent testing laboratories - the firms that send technicians to job sites to verify concrete quality - use it as a baseline qualification for entry-level field staff. Ready-mix concrete producers, general contractors managing large commercial or civil projects, and precast manufacturers all hire to this credential.
The certification is also frequently listed as a contract requirement for federally funded construction. If a project requires documentation that fresh concrete testing was performed by a qualified technician, ACI Grade I is often the specific qualification named in the spec. That context gives this credential unusual staying power in the hiring market compared to general construction certifications.
Once certified, your credential is valid for five years. Recertification requires passing both the written and performance exams again - there is no continuing education alternative that allows you to renew without retesting. After expiration, a one-year grace period exists before the certification lapses entirely. Review the ACI Certification Renewal: Step-by-Step Guide 2027 well before your expiration date to understand the timeline and retesting requirements.
Cost, Funding, and Certification Timeline
Exam fees are set independently by each Sponsoring Group, so the total cost varies by location. The typical range runs from approximately $450 to $660 or more for a single exam attempt. There are no prerequisites - no education requirements, no minimum years of experience - so anyone can sit for the exam. ACI's position is that the exam verifies competency; acquiring that competency through training, on-the-job experience, or self-study is the candidate's responsibility.
For eligible veterans, the ACI Foundation offers a $250 rebate on exam fees. The certification is also eligible for GI Bill reimbursement, which can significantly offset costs for transitioning service members entering the construction trades. Check with your Sponsoring Group and your VA education benefits coordinator early - some groups require paperwork submitted before the exam date to qualify for reimbursement processing.
If you want a detailed look at what the performance exam day looks like from registration through score receipt, the article ACI Performance Exam: What to Expect on Test Day covers the full sequence. Pair that reading with targeted practice on the ACI Exam Prep platform to address both the conceptual and applied sides of the written exam before you arrive at your Sponsoring Group's test site.
Frequently Asked Questions
No. Both the written and performance components of the ACI Grade I exam are strictly closed book. No reference materials, printed notes, or digital devices are permitted. Your only allowed tool on the written exam is a basic four-function calculator with square root capability.
Policies on partial credit between the two components vary by Sponsoring Group. Some groups allow you to retake only the failed component within a defined window; others require retaking both. Confirm this policy with your specific Sponsoring Group before you register so you understand your options if one component doesn't go as planned.
ASTM C172 is assessed through an oral description during the performance exam. You verbally describe the correct procedure to the examiner - including the required number of portions, timing windows, and exclusion zones at the beginning and end of discharge. The examiner scores your description against the same required steps used for the physical tests.
No. The ACI Concrete Field Testing Technician Grade I exam is administered exclusively in person through ACI's network of Sponsoring Groups. There is no remote, online, or third-party testing center option. You must attend a session hosted by an ACI-authorized Sponsoring Group in your region.
There is no nationally mandated sequence between the written and performance components. However, individual Sponsoring Groups may administer them on the same day or in a specific order within their exam session structure. Check your Sponsoring Group's specific session format when you register.
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