The ACTAR exam is for crash investigators and reconstructionists who want accreditation from the Accreditation Commission for Traffic Accident Reconstruction. It has a Theory portion of 75 questions and a Practical case problem with 25 questions and a scaled diagram. You need 75% on both. This page gives you the verified exam facts, free practice sets by topic, worked explanations and a study plan.
Numbers in brackets link to the official sources listed under Sources & last verified. Dates that have passed are removed automatically.
| Item | Detail | Source · Verified |
|---|---|---|
| Number of questions (Practical) | Case problem: 25 questions + scaled diagram[1] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Number of questions (Theory) | 75 questions[1] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Time limit | 4 hours per portion (8 hours total)[2] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Passing score | 75% on both Theory and Practical[1] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Exam fee (Application fee) | $175 (member) / $200 (non-member), non-refundable[3] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Exam fee (Examination fee) | $75 (member) / $125 (non-member)[3] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Retake policy | Retake only the failed part within a 2-year eligibility period; one extra 2-year period allowed (max 3 attempts)[1] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Validity | 5 years[4] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Renewal | 80 CEUs per 5 years + $325 renewal fee[4] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Delivery | In person, proctored, paper & pencil; no computers[2] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Eligibility | Approved application based on training, education & experience[6] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Score release | Up to 60 days; pass/fail only[1] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
| Next exam date | Nov 8, 2026 – Chicago, IL (ACTAR-sponsored)[5] | Accreditation Commission for Traffic Accident Reconstruction · Oct 26, 2026 |
According to Accreditation Commission for Traffic Accident Reconstruction, “The Practical portion consists of a case problem based upon a controlled collision, with a series of twenty-five (25) questions and a scaled diagram for analysis.”[1]
ACTAR accreditation shows that a crash reconstructionist has met a shared standard set by the Accreditation Commission for Traffic Accident Reconstruction. Before you can sit the exam, the commission must approve your application. The review committee looks at your training, education and experience. It pays most attention to accident investigation, reconstruction or engineering courses you have finished with recognized industry providers.
The exam is taken in person with a proctor, on paper with a pencil. Computers are not allowed in the examination room. The Theory portion has 75 questions. The Practical portion is a case problem based on a controlled collision, with 25 questions and a scaled diagram to analyse. You get up to 4 hours per portion, 8 hours in total, with a lunch break between them. To be accredited you must score 75% or higher on both portions. Results can take up to 60 days and are reported as pass or fail only.
The application fee is $175 for members of a Participating Organization or $200 for non-members, and it is non-refundable. The examination fee is $75 for members or $125 for non-members. If you fail one portion, you retake only that portion within your 2-year eligibility period. If needed, you can request an additional 2-year period by paying the applicable fee. Accreditation lasts 5 years, and renewal requires 80 CEUs and a $325 fee. Exam dates and locations change, so check the calendar on actar.org before you book travel. The next listed sitting is Sunday, November 8, 2026, in Chicago, Illinois, before the Midwest Traffic Safety Conference.
The content areas below are copied from the official ACTAR content outline published by Accreditation Commission for Traffic Accident Reconstruction. The right-hand column shows which of our practice sets covers it.
| Official content area | Practice on this site |
|---|---|
| Analytical Methods[1] | ACTAR Speed Calculations Practise choosing the right speed, time and distance equation for the evidence given and solving it by hand, showing each step. |
| Collision Evidence[1] | ACTAR Evidence Documentation & Interpretation Practise reading tire marks, gouges, debris and vehicle damage, and deciding what each piece of evidence can and cannot prove. |
| Core Principles[1] | ACTAR Collision Analysis & Reconstruction Practise the sequence of a collision from perception to final rest, and how each phase is reconstructed from the scene. |
| Foundational Physics[1] | ACTAR Mathematical & Physical Principles o... Practise momentum, energy, friction and vector problems, including signs and directions, until the units and setup feel routine. |
Prepare for the ACTAR - Accreditation Commission for Traffic Accident Reconstructionist exam with our free practice test modules. Each quiz covers key topics to help you pass on your first try.
These are practice questions written for this site, not questions from the real exam. Each explanation shows why the right answer is right and why the others are wrong.
Question: During a head-on collision between two vehicles of equal mass and equal speed, what happens to their combined momentum?
Answer: C. It equals zero
Explanation:
Momentum is mass times velocity, and it has a direction. Vehicles of equal mass moving at equal speed toward each other have momenta of the same size but opposite sign, so the sum is zero. That makes option C correct.
Rule to remember: add momentum as vectors. Give each vehicle a sign or direction before you sum, and expect the total to be conserved, not each vehicle's share.
Question: Which professional attribute is most valued in photogrammetry within the ACTAR field?
Answer: B. Accountability and commitment to standards
Explanation:
Option B is correct. Reconstruction work, including photogrammetry, produces measurements and opinions that other people rely on, so the practitioner has to own the method and follow accepted standards. Accountability means you can show how each measurement was taken, which photographs and reference points you used, and where the limits of the result are.
Rule to remember: in ethics and professional-practice questions, choose the answer that protects accuracy, transparency and the people who rely on your findings.
Question: Which data representation is most appropriate for showing trends over time?
Answer: B. Line graph
Explanation:
A line graph, option B, plots values against time on a continuous axis and joins the points, so rises, falls and turning points are easy to see.
Rule to remember: match the chart to the question. Use a line graph for change over time, a pie chart for shares of a whole, a Venn diagram for overlap and a tree diagram for branching choices. The same idea applies when you plot speed or deceleration against time in a reconstruction.
Start with the official ACTAR preparation guide and the exam page on actar.org, so you know how each portion is built and what the test-day rules are. Then take the practice test once without notes to see where you stand.
Next, work through the sets that match the official content areas. For physics and core principles, use Mathematical & Physical Principles and Vehicle Dynamics. For evidence, use Evidence Documentation & Interpretation, Scene Documentation and Vehicle Damage Analysis. For analytical methods, use Speed Calculations and Crash Dynamics. After each set, reread the explanation for every question you missed and write the formula or rule in your own notes.
The exam is on paper with no computers, so do every calculation by hand. Check the prep guide for which tools you may bring. To rehearse the Practical, work a case problem against a scaled diagram: measure, label and show your steps. Time some sessions in blocks of 4 hours so the length of a portion feels normal. In the last days before the exam, redo the sets where you scored lowest and stop adding new material.
The exam has two portions. The Theory portion has 75 questions. The Practical portion is a case problem based on a controlled collision, with 25 questions and a scaled diagram to analyse. Both are taken in person on paper, and computers are not allowed in the examination room. You get up to 4 hours for each portion, with a lunch break between them.
You need 75% or higher on both the Theory and the Practical portion to be accredited. A high score on one portion does not make up for a low score on the other. Results are released as pass or fail only, and the review can take up to 60 days, so you will not get your result on the day.
The application fee is $175 if you belong to a Participating Organization or $200 if you do not, and it is non-refundable. The examination fee is $75 for members or $125 for non-members. After accreditation, renewal costs $325 at the end of each 5-year term. Check actar.org for current fees before you apply.
You retake only the portion you failed, within your 2-year eligibility period. You do not need to sit the portion you already passed again. If you are still unsuccessful, you can request an additional 2-year eligibility period by paying the applicable fee. The official prep guide sets out the full retake rules, so read it before you register again.
You need an approved application first. The review committee looks at your training, education and experience. It pays most attention to accident investigation and reconstruction courses, or engineering courses, from recognized providers such as Northwestern University's Center for Public Safety. Use the checklist on actar.org to confirm that your records will meet the committee's expectations.
Passing both portions gives you a 5-year accreditation term. To renew, you need 80 CEUs during that period, you agree to follow the ACTAR Code of Conduct, and you pay a $325 renewal fee. Keep a record of your continuing education as you go, so renewal does not depend on finding old certificates at the end of the term.
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