2.2 Written Knowledge Versus Performance Skill

ACI Concrete Field Testing Technician Grade I Study Guide Exam

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1 Orientation: Certification Requirements, Written Exam, Performance Exam, and Study Sources

1.1 Credential Purpose and Official Definition 1.2 Eligibility and the Two-Part Certification Path 1.3 Written Exam Format and Dual Passing Rule 1.4 Performance Exam Format and Grading 1.5 Current Study Sources and CP-1 41st Edition 1.6 Validity, Recertification, and Myth Control

2 JTA, Performance Checklists, Common Fail Points, and Field Mindset

2.1 JTA as the Exam Blueprint 2.2 Written Knowledge Versus Performance Skill 2.3 Performance Checklists and the Six Demonstrations 2.4 Timing, Sequence, and Verbal Description Discipline 2.5 Common Fail Points and Result Recording 2.6 Field Mindset, Exam Habits, and Second Trials

3 ASTM C172: Sampling Fresh Concrete and Field Sample Control

3.1 Representative Sampling Purpose and Exam Role 3.2 Sampling Locations and Middle-Discharge Control 3.3 Composite Sample Timing, Remixing, and Protection 3.4 Sample Size, Large Aggregate, and Wet Sieving 3.5 Sequence With Slump, Temperature, Air, Density, and Specimens 3.6 Performance Exam Verbal Description and Field Habits

4 ASTM C1064 Temperature and ASTM C143 Slump

4.1 ASTM C1064 Purpose, Equipment, and Timing 4.2 Sensor Placement, Stabilization, and Reporting 4.3 Temperature Field Errors and Performance Habits 4.4 ASTM C143 Scope, Equipment, and Setup 4.5 Filling, Rodding, Lifting, and Measuring Slump 4.6 Invalid Slump Results, Reporting, and Integrated Habits

5 ASTM C138: Density, Unit Weight, Yield, and Gravimetric Air

5.1 Purpose, Equipment, and the Calibrated Measure 5.2 Sampling, Filling, and Consolidation Choice 5.3 Strike-Off, Cleaning, Mass, and Density 5.4 Yield, Relative Yield, and Batch Comparison 5.5 Gravimetric Air and Theoretical Density 5.6 Reporting, Validity, and Calculation Traps

6 ASTM C231: Pressure Air Method, Type B Meter, and Aggregate Correction

6.1 Scope, Principle, and When Pressure Air Fits 6.2 Type B Meter Equipment, Calibration, and Setup 6.3 Sampling, Bowl Filling, Consolidation, and Strike-Off 6.4 Type B Sequence: Water, Petcocks, Pressure, and Reading 6.5 Aggregate Correction Factor and Final Air Content 6.6 Reporting, Validity, and Invalid-Result Traps

7 ASTM C173: Volumetric Air Method, Rollameter, Alcohol Correction, and Validity

7.1 Scope, Equipment, and When the Volumetric Method Fits 7.2 Sample, Bowl Filling, Consolidation, and Strike-Off 7.3 Water, Alcohol, Initial Liquid Level, and Sealing 7.4 Inversion, Shaking, Rolling, and Air Release 7.5 Reading Agreement, Out-of-Range Steps, and Invalid Results 7.6 Alcohol Correction, Calculation, Reporting, and Performance Habits

8 ASTM C31: Making and Curing Cylinders and Beams, Initial Curing, and Transport

8.1 Purpose, Sample, Equipment, and Specimen Plan 8.2 Cylinder Molding, Consolidation, Finishing, and Identification 8.3 Beam Molding, Flexural Specimens, and Finishing 8.4 Initial Curing, Protection, Temperature, and Moisture 8.5 Standard Curing, Field Curing, Final Curing, and Interpretation 8.6 Transport, Lab Handoff, Reporting, and Common Failures

9 Integrated Field Workflow: Test Order, Documentation, and Quality Control

9.1 Field Sample to Report Workflow 9.2 Test Order and Parallel Timing 9.3 Documentation and Report Accuracy 9.4 Invalid Results and Retest Decisions 9.5 QA/QC Communication and Acceptance Context 9.6 Contamination, Delays, and Handoff Control

10 Written Exam Strategy: Numerical Values, Calculations, and Category Scoring

10.1 One-Hour Written Exam Pacing 10.2 Category Scoring and the No-Compensation Rule 10.3 High-Yield Numerical Values and Units 10.4 Density, Yield, and Gravimetric Air Calculations 10.5 Air Content Corrections and Validity Checks 10.6 Method-by-Method Practice Plan

11 Performance Exam Strategy: Equipment Setup, Examiner Communication, and Remediation

11.1 Performance Exam Map and Mindset 11.2 Equipment Setup, Station Control, and Safety 11.3 Examiner Communication and Speaking the Work 11.4 One-Step Errors, Timing, and Method Control 11.5 C172 Verbal Description Under Pressure 11.6 Remediation, Retest Planning, and Field Confidence

12 Final Review: Recertification, Career Paths, and Next ACI Credentials

12.1 Two-to-Six Week Final Review Plan 12.2 Final Week and Test-Day Checklist 12.3 CP-1, JTA, and Source Control 12.4 Recertification, Five-Year Cycle, and Re-Exam Requirement 12.5 Career Paths After Field Testing Grade I 12.6 Next ACI Credentials and Growth Map

2.2 Written Knowledge Versus Performance Skill

Key Takeaways Explain This Topic AI

The written exam is closed-book, one hour, and 55 multiple-choice questions, with five to ten questions on each required ASTM standard.

Written passing requires at least 60% on each individual method or practice AND a minimum of 70% overall.

The performance exam checks whether the candidate can correctly perform six methods and verbally describe C172/C172M sampling under examiner observation.

A complete plan pairs recall, explanation, hands-on procedure, and result recording rather than treating written and performance prep as the same task.

Last updated: June 2026

Two Different Checks of the Same Work

The written and performance exams assess the same body of fresh-concrete testing from different angles, and you must pass both to earn the certification. The written exam is closed book, one hour long, and contains 55 multiple-choice questions , with roughly five to ten questions drawn from each required ASTM standard. It checks whether you can recall and apply required concepts, numeric thresholds, equipment requirements, timing relationships, and reporting rules without notes in front of you.

The performance exam is also closed book, but it checks something different: whether you can physically execute the procedures. You demonstrate six of the required test methods to a certified ACI examiner and give a verbal description of Practice C172/C172M sampling. Knowing a fact and reliably producing the matching motion under observation are two distinct skills, and candidates who confuse them are the ones surprised on exam day.

The Written Passing Rule Is Two Rules

The written score is not a single number. ACI applies a dual standard : you must score at least 60% correct on each individual required test method or practice , AND achieve a minimum of 70% overall . This matters enormously for study strategy. A candidate can answer 70% of the whole exam correctly and still fail by missing too many questions on a single weak standard such as C138 yield or C231 air content.

• Requirement Threshold
• Per-method minimum 60% correct on each standard
• Overall minimum 70% across all 55 questions
• Time limit 1 hour
• Format Closed book, multiple choice

The practical lesson is that you cannot "average out" a weak topic. If air content or yield calculations are your blind spot, raising your strong topics will not rescue you. The dual rule forces balanced preparation across all seven standards.

Building a Plan That Serves Both Exams

A complete study plan layers four activities so that written recall and physical skill reinforce each other:

Recall: drill the numbers, timing limits, and equipment requirements until they are automatic.

Explanation: say out loud why each step exists (why three equal layers, why a specific rod count, why testing begins within 5 minutes), which deepens memory and prepares the C172 verbal description.

Hands-on procedure: physically run each method in the same order you will execute on exam day.

Result recording: finish every practiced method by recording the result, because the performance checklist treats recording as part of the procedure.

The most common preparation failure is lopsided effort: memorizing facts while never touching equipment, or rehearsing motions without understanding why the steps matter. Because the certification requires passing both exams, balanced practice across recall and procedure is not optional. Candidates who explain each step aloud while performing it tend to be ready for both the multiple-choice questions and the examiner's checklist at the same time.

Where Written and Performance Knowledge Diverge

Some knowledge serves only one exam, and recognizing which is which prevents wasted effort. The written exam asks about facts that never appear physically in the performance station, such as the definitions of yield and relative yield, the units used in reporting, the conditions under which a method is invalid, and reporting tolerances. The performance exam, by contrast, can only score what you physically do or verbally describe, so it cannot directly test a buried definition.

• Knowledge type Where it is tested
• Numeric thresholds and timing limits Both exams
• Equipment names and their correct use Both exams
• Definitions (yield, relative yield, density) Written only
• Reporting precision and units Written, reinforced in recording
• Smoothness of physical execution Performance only
• Verbal C172 sampling description Performance only

The overlap column is where your study pays double, so prioritize the shared facts first. A candidate who masters the timing windows, rod counts, and equipment use gains points on both exams from one block of study.

A Note on Confidence Versus Competence

Many candidates feel ready after passing practice written questions, then freeze at the equipment. Written fluency creates a false sense of total readiness. The remedy is to schedule deliberate hands-on rehearsal even when the written practice scores look strong, because the performance exam is a separate gate that book study alone never clears.

A useful rule of thumb is to split preparation time roughly evenly once you can pass written practice sets reliably: every block of book review should be matched by a block of physical procedure rehearsal. If you have access to equipment only intermittently, prioritize the methods you can practice on the days the gear is available, and reserve recall drilling for the days you cannot. This keeps both gates advancing in parallel rather than leaving the performance exam as a last-minute scramble.

The candidates who fail most often are not the ones who lacked knowledge; they are the ones who treated the two exams as one and never built the physical fluency the checklist demands.