HEO-B Exam Domains 2026: Complete Guide to All 6 Content Areas

What This Assessment Actually Is

Before breaking down the content areas, it helps to pin down exactly which credential we are discussing. On this site, "HEO-B" is shorthand for the Heavy Equipment Operator: Backhoe assessment from the National Center for Construction Education and Research (NCCER), delivered through the National Craft Assessment and Certification Program (NCACP) under assessment code AEN22BACKH03. The abbreviation "HEO-B" itself is a workflow label used here, not an official NCCER exam code, so don't expect to see it printed on your results.

The published assessment specification, updated February 2024, describes a closed-book written test of 75 items with a two-hour limit. Candidates may use a basic-function, non-printing calculator, but no extra papers, books, notes or other study materials. The specification states a minimum passing score of 75 without explicitly labeling it a percentage, so read it as the issuer's stated threshold and confirm how your results are reported when you test. For a deeper look at that threshold, see our guide to the HEO-B passing score.

If you are still getting oriented on the credential itself, What Is HEO-B Certification? covers the basics, and this article assumes you already know you want to test and need to understand what the exam covers.

The Six Domains and Their Item Counts

NCCER publishes item allocations rather than percentage weights for this assessment, and this guide follows that convention. The table below reproduces the published domains, the curriculum modules they draw from, and the number of items assigned to each.

The module numbers are useful because they tell you where to look in the Heavy Equipment Operations curriculum. Two domains (Grades and Site Work, and Earthmoving and Soils) draw from two modules each, which means their questions can come from more than one chapter of your training materials.

Domain 1: Heavy Equipment Safety

This is the smallest domain at 5 items, built on module 22102. It would be easy to skim, and that is a mistake for two reasons. First, five items is still five chances to gain or lose ground when the pass line is a fixed score. Second, safety reasoning is the sort of knowledge that bleeds into operating scenarios, where the correct answer is often the one that keeps people and utilities safe.

Because the domain is compact, study it quickly and early, then revisit it as you work through backhoe operating questions. When a Backhoe Operations scenario involves stabilizers, slopes or nearby workers, the safe answer is usually the intended one.

Domain 2: Basic Operational Techniques

Basic Operational Techniques carries 10 items from module 22104. This is the general-purpose operator knowledge that applies across heavy equipment before you get into backhoe-specific work: how machines are started, moved, controlled and shut down, and the fundamentals of working a machine productively.

Candidates with seat time often find this domain comfortable but should still read the curriculum language. The exam uses standardized terminology, and a term you know by a different jobsite nickname can trip you up. Pair this domain with the sequencing advice below, since it builds the vocabulary that makes later modules easier to absorb.

Domain 3: Grades and Site Work

With 15 items drawn from modules 22106 and 22210, Grades and Site Work is the second-largest domain. This is where reading the job becomes as important as running the machine. Candidates need to interpret grade information, understand how elevations and slopes relate to the work being performed, and connect that to practical site tasks.

Grades and Site Work overlaps naturally with the math domain. A candidate comfortable with elevation differences and slope relationships will find both areas easier. For a sense of how demanding this overall mix is, read How Hard Is the HEO-B Exam?

Domain 4: Earthmoving and Soils

Earthmoving and Soils holds 10 items from modules 22201 and 22308. Backhoe work is ultimately about moving and handling earth, so understanding what that material is and how it behaves is central. Different soils dig, stand, haul and compact differently, and those differences affect both technique and safety.

Soils knowledge also reinforces safety thinking. Unstable material near an excavation is a hazard, and a candidate who understands why certain soils behave badly will answer related safety and operations questions with more confidence.

Domain 5: Excavation Math

Excavation Math contributes 10 items from module 22207. The exam permits a basic-function, non-printing calculator, so this domain is about knowing which calculation applies and setting it up correctly rather than doing long arithmetic by hand. Do not treat the calculator allowance as a guarantee that math will be trivial: the challenge is choosing the right formula and unit conversion.

Candidates who dread this domain often find that it is more learnable than the fear suggests, because the problem types are repetitive. Ten items is meaningful on a 75-item test, so building a small bank of worked examples is time well spent.

Domain 6: Backhoe Operations

This is the heart of the assessment: 25 items from module 22303, more than any other domain. If you can only perfect one area, this is it. The questions center on the backhoe loader as a machine and as a tool for specific jobs, covering both the loader and the backhoe ends.

Because this domain is worth so much, it rewards scenario practice. Rather than memorizing component names alone, practice answering "what would you do next?" and "what is wrong in this situation?" questions. Original scenario drills for this area are a major focus of the practice material on the main HEO-B practice test site, and our HEO-B study guide shows how to fold them into a full plan.

Third-Edition Assessment, Fourth-Edition Training

One wrinkle that confuses candidates: the published assessment specification explicitly references the third edition of the Heavy Equipment Operations curriculum, while NCCER's current craft catalog also promotes a fourth-edition 2024 training curriculum. The two are not interchangeable assumptions. The assessment's stated references govern what the specification says it is built on.

Practically, this means two things. If your training program uses fourth-edition materials, the core topics still map well to the six domains, but you should check your sponsor or testing site about which edition the version of the assessment you booked relies on. And if you are buying or borrowing study materials, confirm the edition and be aware that module numbering and chapter organization can differ between them. Do not assume a fourth-edition chapter number lines up with the module numbers in the table above.

Sequencing Your Study by Domain

You do not need a generic study philosophy here; you need an order that respects how these domains build on each other and where the points are. The plan below front-loads vocabulary and safety, spends the most time where the item counts are largest, and saves full-length timed practice for last.

Adjust the pace to your own schedule and experience; operators with extensive backhoe seat time may compress Weeks 1 and 4, while candidates newer to the machine may stretch Backhoe Operations across more sessions. When you review misses, tag each by domain so you can see whether weakness is concentrated in the big domains or scattered. The HEO-B cheat sheet works well as a final-day review of the facts you tagged.

Written Assessment vs. Performance Verification

The six domains above describe the written knowledge assessment. NCCER also offers a corresponding hands-on Performance Verification, which is separate from the two-hour written exam. Its current task count, duration and detailed scoring were not verified for this article, so check with your testing sponsor before assuming what it entails.

The important point for candidates is that these are different things. Passing the written assessment alone should not be described as completing every practical qualification, and employers who care about demonstrated machine skill may want to see the practical side as well. Credentials earned through either route are accessible through your NCCER Account, along with score results and a training prescription that points out where to improve. That training prescription is genuinely useful if you need to retest, because it shows where your gaps were. Understanding who recognizes these credentials is covered in our look at HEO-B jobs.

Fees and Logistics to Confirm

No single universal candidate fee was verified from the issuer. One provider lists $80 for NCCER members and $85 for non-members for a two-hour backhoe assessment, but that listing uses a legacy "Backhoe V2" title and a local course code, so treat it as one provider's quote rather than a standard price. Always confirm which assessment version you are booking and whether practical or administration charges apply separately. Our certification cost breakdown goes deeper, and you can read about eligibility in the requirements guide.

Frequently Asked Questions

With the six domains mapped and item counts in hand, you can aim your preparation where the points are. For more on timing your attempt, see HEO-B exam dates and scheduling, and when you are ready to test your knowledge, head to the practice test hub.