DANB (RHS) Exam Practice Test

The Dental Assisting National Board, Inc’s (DANB) Radiation Health and Safety (RHS) Exam is one of the examinations required for National Entry Level Dental Assistant (NELDA) and Certified Dental Assistant (CDA) certifications. There are no eligibility requirements for the RHS exam, and candidates may apply to take the exam during the application acceptance window (usually one calendar year). Thirty-seven states either recognize or require the RHS examination for licensure.


The purpose of the Radiation Health and Safety examination is to measure a candidate’s knowledge of national radiographic imaging practices and proper safety procedures utilizing radiographic equipment.

Test design

The RHS exam is an adaptive computer-delivered assessment consisting of 100 multiple-choice questions. The first question of the exam starts at the minimum pass point. If you answer the question correctly, the next question is more challenging. If answered incorrectly, the next question will lessen in difficulty. Basically, the computer adapts to your knowledge and challenges the upper and lower levels of your abilities. Your score will be determined by the difficulty of the questions you answered correctly.

 The questions for the examination are divided into four domains:

  • Expose and evaluate – 26% of the exam

In this domain, your knowledge of assessment and preparation, acquisition of radiographic images, evaluation of radiographic images, and patient management throughout the radiographic procedure is assessed.

  • Quality assurance and radiology regulations – 21% of the exam

This domain evaluates your knowledge and abilities in quality assurance and regulations regarding radiology.

  • Radiation safety for patients and operators – 31% of the exam

Your knowledge of American Dental Association (ADA) guidelines for patient selection and limiting radiation exposure is evaluated. Additionally, your knowledge of the principles of radiation protection, the operation of equipment, patient safety, and monitoring of radiation exposure is assessed.

  • Infection control – 22% of the exam

Your knowledge and understanding of infection control techniques, regulatory body guidelines (such as ADA, Centers for Disease Control and Prevention, and OSHA), and precautions for patients and operators are examined.

You are given 75 minutes for the exam and 10 minutes for a tutorial and ending comments.

Registration, cost, and location

You can register for the RHS exam at any time online, by fax, or by mail. As a part of the registration process, you select the date, time, and location of your exam. The test is delivered at authorized Pearson VUE test centers located nationwide.

The registration fee for the RHS exam is $270.00 for candidates employed in Maryland, $245.00 for active duty military personnel, and $250.00 for all other exam candidates. The registration fee includes a non-refundable $75.00 processing fee.

Test Day

Arrive 15 to 30 minutes before your testing appointment to allow time to store your belongings in the provided locker, and complete the pre-test paperwork. Test center staff verifies your identification, takes your digital photograph, and escorts you to your testing station.

At your station, everything you need for the exam is provided. You will take a short tutorial about the delivery method and once complete, your test begins.

If you have any questions or need to take a break, raise your hand and a test proctor will come to you. If you need to take a break, the proctor will gather your materials and escort you out of the testing center. Keep an eye on the time you spend away from the test as your time does not pause while you are away.

If time remains after you answer the last question, review your answers. Once you are satisfied with your responses, submit your exam for scoring. The test proctor will escort you out; re-entry after completion of your exam is not allowed.

Exam scoring and results

The Radiation Health and Safety certification examination is an adaptive exam – question difficulty increases with each correct answer. The average candidate will answer 50% of the questions correctly. Your score is determined by the difficulty of the question presented and passed. The score scale is 100 to 900, with 400 the passing point.

Before your departure from the testing facility, you will receive an unofficial score report indicating pass or fail status. Two to three weeks after your exam, your official score report will arrive in the mail. If you failed the exam, your score report includes performance information for each content area.

You may retake the exam as many times as needed to receive a passing score. Keep in mind that each retake requires submission of documentation and the exam registration fee. Some states may require additional education after a number of failed attempts.

How Can I Prepare for the DANB (RHS) Test?

That’s a great question.  We’ve broken down the answer into three parts.

  1. Do yourself a favor and study.  Do not walk in unprepared. We have recommended prep materials below, but that only helps if you actually try.  Plus, studying is actually proven to be the best antidote to test anxiety.
  2. Take care of yourself.  Make sure you’re eating well, exercising, and sleeping.  All of these things are scientifically linked to brain performance.  If you take care of your body, you’ll be helping your grades.
  3. Get a study guide or set of flashcards.  Some people study better a certain way. Find your study strengths and make the most of them.  We’ve tried to make it easy for you by tracking down the best study guide and flashcard set for your exam.  Below you’ll see links to both!

Study Guide



Last Updated: July 31, 2019