Radiation Health and Safety (RHS) Exam Outline

Overview

• Part of the National Entry Level Dental Assistant (NELDA) and Certified Dental Assistant (CDA) certification programs.
• No eligibility requirements to take the RHS exam.
• Ensures national standard competence in radiation health and safety for patient and healthcare worker safety.

Exam Content

• Focus on digital radiography since July 7, 2022.
• No conventional, film-based concepts.

NELDA Component Exams

• Anatomy, Morphology and Physiology (AMP)
• Radiation Health and Safety (RHS)
• Infection Control (ICE)

CDA Component Exams

• Radiation Health and Safety (RHS)
• Infection Control (ICE)
• General Chairside Assisting (GC)

Exam Details (Effective 03/12/2025)

• Removal of CBCT and cephalometric image acquisition from the outline.
• Candidates still need to know the purpose of these images.

Exam Weighting by Domain

1. Purpose and Technique (50%)
2. Radiation Characteristics and Protection (25%)
3. Infection Prevention and Control (25%)

Exam Characteristics

• 75 multiple-choice questions.
• 60 minutes for the exam, 65 minutes for the appointment.
• Available in-person or through remote proctoring.
• Uses computer adaptive testing (CAT) for scoring.

RHS Exam Outline

I: Purpose and Technique (50%)

• Anatomical landmarks and materials on images: apical pathology, caries, dental anomalies, etc.
• Purpose of dental images: periapical, bitewing, full mouth series, etc.
• Procedures and techniques: patient preparation, positioning, error correction, and image viewing.
• Legal requirements: HIPAA compliance, image retention, etc.

II: Radiation Characteristics and Protection (25%)

• Radiation physics: factors affecting x-ray production, characteristics, and absorption.
• Radiation biology: cell sensitivity, biological effects, and measurement units.
• Radiation protection: dose limits, exposure guidelines, and protection factors.

III: Infection Prevention and Control (25%)

• Standard precautions: for equipment, supplies, patient, and operator safety.
• Disinfection and sterilization: of instruments and prevention of cross-contamination.

Suggested References

• Primary Textbooks:

  1. Modern Dental Assisting by Bird & Robinson
  2. Dental Radiography by Ianucci & Howerton
  3. Essentials of Dental Radiography by Thomson & Johnson

• Infection Control: Infection Control and Management by Miller

• Additional Resources: CDC, OSHA guidelines, DALE Foundation, ADAA courses.

Acronyms and Radiography Terms

• List of acronyms and terms relevant for understanding radiography and dental safety.

Exam Development and Maintenance

• Developed annually by subject matter experts, informed by a job analysis survey.
• Passing standard set through a Standard Setting Study using the Angoff method.

Receiving Exam Results

• Results available within 1-3 business days via DANB account.

State Regulations

• State dental boards regulate duties; passing the exam does not automatically grant authority in all states.