- The legacy "Nozzleman (Dry-Mix Process)" title is now officially ACI Shotcreter (Dry-Mix Process); the content is the same dry-mix credential.
- Written exam: closed book, 60-90 questions, 90 minutes, 75% to pass. The practical is separate.
- Performance Part II fails if any core grades above 3 or more than two cores grade 3.
- Full certification needs 500 verified hours, with at least 200 hand-nozzling; trainee status needs 25 hand-nozzling hours.
Identity and Name Check
Before memorizing anything, make sure you are studying the right credential. This sheet covers the ACI Shotcrete Nozzleman (Dry-Mix Process) certification, issued by American Concrete Institute International (ACI). ACI's current official title is Shotcreter (Dry-Mix Process). The older "nozzleman" wording still circulates in job postings, sponsor materials, and search results, but you are preparing for the same dry-mix credential under either name. For the background on the title, see What Is Shotcrete Nozzleman (Dry-Mix)?
Testing is delivered through ACI-approved sponsoring groups and examiners. The American Shotcrete Association (ASA) is a delivery sponsor, not the issuer. ASA's program page also lists a Prometric option for the English written examination, while the practical is always separate. Our overview of Shotcrete Nozzleman (Dry-Mix) certification covers the credential's purpose in more depth.
Exam Format at a Glance
The credential has two assessment halves, and candidates often prepare for only one.
Written Examination
- Closed book.
- Between 60 and 90 questions, with 90 minutes allowed.
- 75% required to pass.
- ASA's program page describes multiple-choice questions; ACI's policy permits true/false or multiple-choice items. No single exact question count is assigned within the 60-90 range, so do not trust anyone quoting one fixed number.
Performance Examination
- Closed book and hands-on.
- Requires vertical dry-mix placement. Overhead placement is an additional certification orientation.
- Part I is a workmanship checklist needing at least 75%.
- Part II evaluates five cores (details below).
The written exam and both performance parts must be completed within one year. For a candid look at what makes each half challenging, read How Hard Is the Shotcrete Nozzleman (Dry-Mix) Exam?
The Numbers Table
These are the figures worth committing to memory, drawn from ACI's certification policy and program details.
| Item | Fact |
|---|---|
| Issuer | American Concrete Institute International (ACI) |
| Written exam | Closed book; 60-90 questions; 90 minutes |
| Written passing mark | 75% |
| Performance Part I | Workmanship checklist; at least 75% |
| Performance Part II | Five cores; fail if any core is graded above 3, or more than two cores receive grade 3 |
| Completion window | Written plus both performance parts within one year |
| Full certification experience | 500 verified hours as a shotcreter, including at least 100 hours in each process and orientation sought and at least 200 hours of direct hand-nozzling |
| Trainee experience | At least 25 verified hand-nozzling hours in the process; vertical only |
| Education prerequisite | None imposed by ACI |
| Certification term | Five years |
A frequent error: reading the 500-hour requirement as 500 hours of hand-nozzling. It is not. Only 200 of those hours must be direct hand-nozzling. A fuller treatment of eligibility lives in Shotcrete Nozzleman (Dry-Mix) Requirements, and the exact thresholds are explained in Shotcrete Nozzleman (Dry-Mix) Passing Score.
Ten Domains, One Page Each
ACI's required knowledge areas are listed as ten unweighted headings. They are supported by the April 2025 Job-Task Analysis (JTA) for ACI Certification of Shotcreter, but no percentage blueprint is published, so do not trust any site that quotes domain weights. Treat all ten as fair game. For the full breakdown, see Shotcrete Nozzleman (Dry-Mix) Exam Domains: Complete Guide to All 10 Content Areas.
Domain 1: Basic concrete technology
The dry-mix process still obeys concrete fundamentals.
- Cement, aggregate gradation, admixtures, and supplementary cementitious materials and how each affects the mixture.
- Water-cementitious materials ratio concepts and why water control matters differently when water is added at the nozzle.
- Moisture content of the bagged or bulk dry material and its effect on hose conveyance.
Domain 2: Shotcrete Equipment
Dry-mix equipment is a system, and the written exam expects you to know what each part does.
- Delivery equipment, hoses, nozzle body, water ring, and air supply.
- How air volume and pressure affect velocity, rebound, and compaction.
- Maintenance and cleanup, including how blockages form and how they are cleared safely.
Domain 3: Environmental conditions and precautions
Weather and ambient conditions change placement behavior.
- Hot, cold, windy, and wet conditions and the precautions each requires.
- Protection of fresh material from freezing, rapid drying, and washout.
Domain 4: Inspection and preparation of surfaces
Bond starts before the first pass.
- Substrate cleanliness, condition, and moisture state at the time of placement.
- Forms, ground wires or guides, and reinforcement checks before shooting.
Domain 5: Shotcrete placement, principles, and techniques
The heart of both exam halves.
- Nozzle distance, angle, and motion for compaction and encapsulation of reinforcement.
- Rebound and overspray: what causes them, where they collect, and why trapped rebound is a defect.
- Sequencing, thickness build-up, and handling corners, congested bars, and sags.
Domain 6: Communication
Dry-mix crews work with limited visibility and loud equipment.
- Signals and protocols between nozzleman, equipment operator, and crew.
- Reporting problems and conditions to supervision and inspection.
Domain 7: Finishing and tolerance controls
- Screeding, cutting, and finishing methods, and when each is appropriate.
- Thickness and line-and-grade tolerance concepts.
Domain 8: Safety
- Personal protective equipment, hose and pressure hazards, and dust and silica exposure.
- Safe response to blockages and safe handling of cement-containing materials.
Domain 9: Testing/quality
- Core and panel evaluation, and what grading criteria are looking for in the finished material.
- Recognizing and documenting defects such as voids, sand pockets, and laminations.
Domain 10: Curing
- Why early moisture retention matters for strength and durability.
- Methods and timing for curing placed shotcrete.
Performance Test Grading
The practical is where preventable failures happen, mostly from misreading the grading rule.
Part I is separate: a workmanship checklist where you need at least 75%. Think of Part I as your technique and process score and Part II as the proof of what ended up in the wall or panel. A candidate with tidy technique can still fail on a void-laden core, and the reverse is also possible. The first-time female ACI-certified nozzleman account in Shotcrete magazine (Fourth Quarter 2025) is a useful read on how the practical feels from the nozzle side, and it also corroborates the nozzleman-to-shotcreter rename.
Core-quality habits to rehearse: consistent nozzle distance, steady perpendicular orientation, deliberate encapsulation of bars from the back, and constant attention to rebound pockets. For difficulty context without invented numbers, see Shotcrete Nozzleman (Dry-Mix) Pass Rate, which explains why no verified national pass rate should be quoted.
Trainee vs Full Certification
| Feature | Shotcreter-in-Training | Full Dry-Mix Certification |
|---|---|---|
| Hand-nozzling hours | At least 25 verified hours in the process | At least 200 hours direct hand-nozzling within the 500 |
| Total experience | 25 hours | 500 verified hours as a shotcreter, with at least 100 in each process and orientation sought |
| Orientation | Vertical only | Vertical, with overhead as an added orientation |
| Upgrade path | Adding 475 qualifying hours can upgrade, but only for the remainder of the original certification term | Full five-year term |
The trainee path is a stepping stone, not a shortcut. The upgrade arithmetic (25 + 475 = 500) is a favorite trap on forums, but the upgrade does not restart a fresh five-year clock. If you are weighing the two routes, Shotcrete Nozzleman (Dry-Mix) Training outlines how crews build hours toward full certification.
Renewal and the ACI/ASA Hour Discrepancy
Certification lasts five years. Renewal requires either:
- The then-current written and performance examinations plus applicable experience requirements; or
- An eligible structured-interview-plus-performance route.
For the interview route, ACI requires prior certification in the same process issued within six years and at least 500 work hours in the preceding two years, including 100 in each process and orientation sought.
ASA also requires its education/refresher training for initial certification and recertification, with stated exceptions for retests and adding an orientation. Those are sponsor requirements, separate from ACI's own education and experience rules.
Budgeting by Component
ASA's currently linked December 2024 fee file lists charges as separate components in USD, shown as ASA-member / non-member:
| Component | Member / Non-member |
|---|---|
| Written examination (per person) | $250 / $360 |
| Vertical performance examination | $120 / $160 |
| Additional overhead performance examination | $120 / $160 |
| Session setup | $800 / $950 |
| Session day | $2,850 / $3,550 |
| Study materials | $70 / $110 |
These are building blocks, not an all-inclusive candidate price. Session, equipment, materials, coring, and other applicable costs must be budgeted separately, and the share assigned to an individual depends on how the session is organized. A crew-wide session spreads setup and day charges very differently than a single candidate would experience. Our Certification Cost breakdown walks through how to assemble a realistic total.
On pay, keep local job-market evidence separate from any claimed certification premium. A certification may help you get hired or bid work, but a specific pay bump attributable to the credential is not established. The Salary Guide and the ROI analysis treat that distinction carefully.
A Domain-Ordered Review Schedule
If you have about four weeks before your written exam, sequence the domains by dependency, not alphabetically. Concrete technology comes first because everything else builds on it.
Foundations
- Domain 1 (basic concrete technology) and Domain 2 (equipment).
- Learn how water control and air supply interact in the dry-mix process.
Site and technique
- Domains 3, 4, and 5: conditions, surface preparation, and placement principles.
- Spend extra time on rebound, overspray, and reinforcement encapsulation.
Coordination and finish
- Domains 6, 7, and 8: communication, finishing and tolerances, safety.
Verification and mock review
- Domains 9 and 10: testing/quality and curing.
- Full-length timed practice, then rework weak domains.
ASA links the fourth-edition CP-60 Shotcreter Craftsman Workbook (English and Spanish), including CCS-4, Shotcrete for the Craftsman, as current courseware. Use the official workbook as your primary reference; the public JTA is useful for scope, but it is not a substitute for the workbook. For the fuller plan, see the Shotcrete Nozzleman (Dry-Mix) Study Guide, and drill with the practice test.
Original Practice Questions with Explanations
These are original teaching items written for review, not recalled exam content. Marketplace "verified answer" sets are not authenticated examination material, so treat them with caution.
Question 1 (Domain 5)
A nozzleman notices a pocket of rebound collecting behind a rebar mat. What is the correct response?
- Answer: Remove the trapped rebound before continuing; do not shoot over it.
- Why: Rebound trapped in the section creates voids and weak zones. Cleaning it out is part of proper encapsulation.
Question 2 (Domain 1)
In dry-mix shotcrete, who controls the water content at the point of placement?
- Answer: The nozzleman, by adjusting water at the nozzle.
- Why: This is the defining difference from wet-mix, and it is why nozzleman skill is so central to consistency in the dry-mix process.
Question 3 (Performance grading)
A candidate receives grades of 3, 3, 3, 2, and 1 on five cores. Result?
- Answer: Fail.
- Why: More than two cores graded 3 is a failure, even though no core exceeds 3.
Question 4 (Requirements)
True or false: all 500 required hours for full certification must be direct hand-nozzling.
- Answer: False.
- Why: The 500 hours are experience as a shotcreter, with at least 100 in each process and orientation sought and at least 200 of direct hand-nozzling.
More item types and scenario drills are available in the main practice test. If you are unsure which paperwork or schedule applies to you, Exam Dates, Deadlines & Scheduling explains how sponsor-run sessions affect timing.
FAQ
Yes. ACI's current official title is Shotcreter (Dry-Mix Process); the legacy nozzleman wording refers to the same dry-mix credential and is still widely used by sponsors and employers.
The written exam allows 60 to 90 questions in 90 minutes, closed book, with 75% needed to pass. No single exact count is assigned within that range, and question types may be multiple-choice or true/false.
No. The written exam is only one component. You must also pass the two-part performance examination (workmanship checklist and five-core evaluation), meet the experience requirement, and complete everything within one year.
ACI imposes no specific education prerequisite. Experience hours are the gate. Separately, ASA as a sponsor requires its own education or refresher training for initial certification and recertification.
ACI's interview route requires at least 500 work hours in the preceding two years, while ASA's sponsor policy states 1,000 hours for its written-exam waiver. Confirm directly with your sponsor which requirement governs your session before booking.