The DANB RHS Exam Overview
The Radiation Health and Safety (RHS) exam is a national requirement for dental assistants seeking to advance their careers. Whether you are aiming for your CDA or just need your state’s X-ray certification, this is the hurdle you must clear.
| Exam Feature | Details (2026 Standards) |
|---|---|
| Number of Questions | 100 Multiple Choice |
| Time Allotted | 75 Minutes |
| Passing Score | 400 (on a 200-900 scale) |
| Standard Fee | $285 |
⚠️ 2026 EXAM UPDATE:
The DANB RHS exam now reflects the ADA/AAOMR guidelines which state that lead aprons and thyroid collars are no longer mandatory for routine dental radiographs. Expect questions regarding this change in the Safety domain!
The DANB RHS exam now reflects the ADA/AAOMR guidelines which state that lead aprons and thyroid collars are no longer mandatory for routine dental radiographs. Expect questions regarding this change in the Safety domain!
Exam Domain Breakdown
The exam is split into three weighted categories. Your study time should mirror these percentages:
50% Technique
Mounting, Error Correction, Landmarks, and Paralleling vs. Bisecting.
25% Safety
ALARA principle, biological effects, and operator protection.
25% Quality
Infection control (Digital sensors) and Legal/HIPAA requirements.
Key Success Tips
- Think Digital: Darkrooms and chemicals are largely gone from the exam. Focus on sensors.
- Learn the Landmarks: You will be shown digital images and asked to identify the Maxillary Sinus, Mental Foramen, etc.
- Practice the Clock: You have less than 1 minute per question. Use our mock exams to build speed.