Part of the expanding PassProfessor catalog: The Radiation Health and Safety examination, known as the RHS, is DANB’s component examination in dental radiography: 75 multiple-choice questions in 60 minutes, delivered by computer-adaptive testing and scored on DANB’s 100-to-900 scaled scale with 400 required to pass. It is one component of DANB’s NELDA and CDA certification programs — passing it alone does not confer the CDA credential. Its outline weights Purpose and Technique at 50%, Radiation Protection at 25% and Infection Prevention and Control at 25%, and it has tested digital radiography only since July 2022.
This program is part of the expanding PassProfessor catalog — join the notify list and we’ll email you when enrollment opens.
The RHS is the examination that stands between a dental assistant and the radiography tasks of the operatory: acquiring diagnostic images, protecting patients and operators from unnecessary exposure, and running infection prevention around every exposure. DANB administers it as a standalone examination and as a component of its certification programs, and many states draw on it in their own radiography rules for dental assistants — which rules apply to you is your state’s question, answered by your state board. The current examination is a digital-radiography examination: film-based concepts have not been tested since July 7, 2022. PassProfessor’s RHS program is in development as part of the expanding PassProfessor catalog, built to DANB’s published RHS outline.
Does passing the RHS make me a Certified Dental Assistant?
No — and DANB’s own outline says why. The RHS is a component examination: it is one part of the National Entry Level Dental Assistant (NELDA) and Certified Dental Assistant (CDA) certification programs, alongside their other components. Passing the RHS earns the RHS examination result and satisfies the radiography component; the CDA credential itself requires completing the full program’s components and requirements. This program prepares you for the RHS examination only, and describes it that way throughout. Separately, whether you may legally take radiographs in your state, and under what supervision, is set by your state’s rules — DANB examination success and state authorization are related but distinct.
What will the program cover?
Practice mapped to the published outline, area by area. The program is being built on the certifying body’s own published content structure for the Radiation Health and Safety (RHS) examination, at the published weights recorded in the table below. Preparation time lands where the examination itself puts the emphasis, instead of spreading evenly across ground the outline treats unevenly.
Results you can read by content area. Because practice will be organized by the outline’s areas, your results can be read area by area — a thin area shows while there is still time to repair it, instead of hiding inside an overall score.
Original questions, written from the outline outward. When the program opens, every question will be an original PassProfessor practice question written to the published outline and current authoritative sources for this field. None will be an actual examination item, a recalled item, or another provider’s material, and no question will ask you to recite a code, section number or citation — knowledge is tested, citations never are.
Timed practice at the real sitting’s shape. The program’s design includes sustained timed practice modeled on the recorded facts of the real sitting — its length and pace as set out in the fact table below — so pacing is trained rather than discovered on the day. That design is PassProfessor’s preparation choice; the real examination’s own facts stand in their own table.
The real exam at a glance
| Fact of record | DANB RHS |
|---|---|
| Examination | Radiation Health and Safety (RHS) |
| Administered by | DANB (Dental Assisting National Board) |
| Questions | 75 multiple-choice questions |
| Time | 60 minutes |
| Delivery | Computer-adaptive testing (CAT) — test center or online proctoring |
| Scoring | Scaled score on a 100–900 scale |
| Passing standard | Scaled score of 400 |
| Content | Digital radiography only (since July 7, 2022) |
| Program role | Component of the NELDA and CDA certification programs |
How will practice map to the outline?
| Content area | Published weight |
|---|---|
| Purpose and Technique | 50% |
| Radiation Protection | 25% |
| Infection Prevention and Control | 25% |
What does Purpose and Technique cover? (50%)
Half the examination. It covers what dental images are for and how diagnostic digital images are acquired: anatomical landmarks, conditions and materials as they appear on images; image receptors and their handling; patient positioning and acquisition technique for intraoral and extraoral imaging, including panoramic and cone-beam imaging; technique modification for anatomical variation and clinical conditions; image quality evaluation and error recognition and correction; and the legal and record expectations around images. Technique questions reward candidates who can reason from a flawed image back to its cause.
How should you prepare for Purpose and Technique? Allocate study time in proportion to its published weight — 50% — and then adjust by evidence: survey the area early, note where your reasoning breaks down, and return with focused practice rather than rereading. The questions in this area reward applied judgment in realistic situations, so preparation should pair every block of reading with questions answered under time, followed by a careful review of why each wrong option was wrong. Keep a running list of the distinctions this area tests most finely; on this outline, small distinctions inside a heavily weighted area are worth more than broad familiarity everywhere.
What does Radiation Protection cover? (25%)
A quarter of the examination on the physics and biology behind safe practice: factors affecting x-ray production (kVp, mA, exposure time, dose), radiation biology and the effects exposure can have, and the protection discipline for patients and operators — shielding, distance and positioning, exposure reduction, monitoring, and the consent and refusal conversations around imaging. ALARA is this domain’s working principle: every exposure justified, every dose as low as reasonably achievable.
How should you prepare for Radiation Protection? Allocate study time in proportion to its published weight — 25% — and then adjust by evidence: survey the area early, note where your reasoning breaks down, and return with focused practice rather than rereading. The questions in this area reward applied judgment in realistic situations, so preparation should pair every block of reading with questions answered under time, followed by a careful review of why each wrong option was wrong. Keep a running list of the distinctions this area tests most finely; on this outline, small distinctions inside a heavily weighted area are worth more than broad familiarity everywhere.
What does Infection Prevention and Control cover? (25%)
The final quarter applies standard precautions to radiography: treatment-room and equipment preparation and breakdown, surface barriers and disinfection, sterilization of items that require it, hand hygiene and personal protective equipment, and prevention of cross-contamination through the imaging workflow — following the ADA, CDC and OSHA expectations DANB’s outline cites. It is tested as radiography-specific practice, not generic infection-control recall.
How should you prepare for Infection Prevention and Control? Allocate study time in proportion to its published weight — 25% — and then adjust by evidence: survey the area early, note where your reasoning breaks down, and return with focused practice rather than rereading. The questions in this area reward applied judgment in realistic situations, so preparation should pair every block of reading with questions answered under time, followed by a careful review of why each wrong option was wrong. Keep a running list of the distinctions this area tests most finely; on this outline, small distinctions inside a heavily weighted area are worth more than broad familiarity everywhere.
What score passes?
DANB scores the RHS on a scaled scale of 100 to 900 and publishes 400 as the passing scaled score. Because DANB uses computer-adaptive testing, the score reflects the difficulty of the questions answered as well as their number; 400 is a scaled score, not 400 of anything and not a percentage, and no practice percentage converts into it. Where this program uses 70 in practice, 70 is a PRACTICE BENCHMARK ONLY — a PassProfessor study target, not DANB’s standard.
Who can take this examination?
DANB states no education or experience eligibility requirement simply to sit for the RHS examination itself; candidates apply, are authorized, and schedule within a 60-day testing window. That openness is about the examination, not about practice rights: state rules govern whether a dental assistant may perform radiography tasks, under what supervision, and whether the RHS (or a state alternative) is required. The RHS is offered in English, Spanish and Vietnamese. Confirm your state’s radiography requirements with your state dental board alongside your DANB application.
How should you use this page while the program is in development?
- Join the notify list today. Enrollment is not open yet, and the notify list is how you hear the moment it is. While you wait, read the DANB RHS exam guide — it walks the outline area by area and lays out eligibility, scoring and study planning in full.
- Study from the official outline now. The published outline quoted on this page is the syllabus; organizing your reading by its areas and weights is useful work today, before any practice program opens.
- When the program opens, survey every area first. Early practice should touch each content area, so your first area-by-area picture of yourself is honest rather than flattering.
- Drill the area that costs you. Let results, not preferences, set the next block of study — outlines reward the candidate with no thin area.
- Finish with timed, mixed practice. Sit full timed practice at the real sitting’s pace, and test when your practice is consistently strong across areas. Any 70 in this program’s practice scoring is a PRACTICE BENCHMARK ONLY — a training marker, never the certifying body’s standard.
Frequently asked questions
What is the RHS examination? DANB’s Radiation Health and Safety examination — a 75-question, 60-minute computer-adaptive examination of dental radiography: image purpose and technique, radiation protection, and infection prevention and control.
Does passing the RHS make me a CDA? No. The RHS is a component examination of DANB’s NELDA and CDA certification programs. Passing it satisfies that component; the CDA credential requires the full program. This program prepares you for the RHS only.
What score passes the RHS? A scaled score of 400 on DANB’s 100–900 scale, as DANB publishes it. It is a scaled score under computer-adaptive testing — not a percentage and not a raw count.
Does the RHS still test film radiography? No. DANB’s outline states that no conventional, film-based concepts have been tested on the RHS since July 7, 2022. The examination tests digital radiography only.
Who may take the RHS? DANB states no eligibility requirement simply to sit for the RHS itself. Whether you may legally take radiographs at work, and under what supervision, is governed by your state’s rules — check with your state dental board.
In what languages is the RHS offered? English, Spanish and Vietnamese, per DANB’s current application packet; the versions follow the same outline and passing standard.
How is the examination delivered? By computer-adaptive testing through DANB’s testing vendor, at a test center or by online proctoring, within a 60-day testing window after your application is approved.
How are the questions weighted? Purpose and Technique 50%, Radiation Protection 25%, and Infection Prevention and Control 25%, per DANB’s published RHS outline.
Are these DANB’s actual examination questions? No. When this program opens, its questions will be original practice questions written by PassProfessor to DANB’s published RHS outline. We never use actual examination items, recalled items, or another provider’s material.
When will enrollment open, and what will it cost? The program is in development as part of the expanding PassProfessor catalog, and no price is stated while it is in development. Join the notify list and the launch email will carry the price and the enrollment link.
Disclaimer
PassProfessor is an independent exam-preparation provider; this program is not endorsed by, affiliated with or sponsored by DANB (Dental Assisting National Board). The credential name is used on this page as a factual reference to the certifying body’s examination. This program is examination preparation only: it provides no certification or license, which the certifying body or licensing authority alone awards to candidates who meet its requirements. Examination details on this page are drawn from the official sources recorded in the companion guide and are current as of November 2026; the certifying body’s official publications govern if anything here differs from them.