DANB Radiation Health and Safety Exam (RHS) Pass Rate, Format & Study Guide

The DANB Radiation Health and Safety (RHS) exam is a component exam of several DANB certifications and is recognized or required in many states for dental assistants who take radiographs. It is issued by the Dental Assisting National Board, Inc. (DANB). The exam has 75 questions and you are given 60 minutes, within a 60-day testing window.

Many state dental boards recognize or require DANB's RHS exam for dental assistants who expose radiographs, and it is a component of DANB's CDA and COA certifications. Passing the RHS exam is a required step for those credentials.

Dental assistants preparing for DANB certification or a state radiography requirement that uses the RHS exam, and candidates retaking it. State requirements vary; check your state board before you apply.

The certifying body does not publicly publish an official pass rate for this exam. Be wary of third-party sites citing a specific number here — treat any pass-rate claim you see elsewhere for this exam as unverified.

DANB's candidate handbook says there is no limit on how many times a failed exam may be retaken; you must reapply and pay the full exam fee each time (search extracts mention a one-time discount on the first retake), and state laws may require additional education after failed attempts.

Passing standard: DANB's Board sets the pass point using standard psychometric procedures for criterion-referenced exams, and a candidate must perform at or above that standard; DANB's candidate handbook does not publish a raw-score cutoff. The exam has 75 questions and you are given 60 minutes, within a 60-day testing window. No official pass rate for this exam was available in the sources we reviewed, so none is quoted here.

The exam has 75 questions and you are given 60 minutes, within a 60-day testing window. Format: 75 questions · 60 minutes · 60-day testing window. Passing standard: DANB's Board sets the pass point using standard psychometric procedures for criterion-referenced exams, and a candidate must perform at or above that standard; DANB's candidate handbook does not publish a raw-score cutoff.

• Purpose and Technique50%
• Radiation Characteristics and Protection25%
• Infection Prevention and Control25%

The content outline spreads questions across 3 areas: Purpose and Technique (50.0%); Radiation Characteristics and Protection (25.0%); Infection Prevention and Control (25.0%).

DANB lists no eligibility requirements for the RHS exam on its exam page; individual states may set their own requirements for taking dental radiographs, so check your state board at danb.org/state-requirements before you apply.

DANB lists a US$270 fee for the RHS exam, which includes a US$75 non-refundable application fee (reported in search extracts of danb.org; the DANB exam page itself does not show the fee). State requirements and any additional education are separate.

After you pass, DANB certifications that include RHS have their own renewal and continuing education requirements; check DANB for the current rules.

Start with the heaviest areas of the content outline: Purpose and Technique (50.0%); Radiation Characteristics and Protection (25.0%); Infection Prevention and Control (25.0%). Then work through the remaining areas, practise jurisdiction-specific rules separately from the general content, and finish with timed full-length practice runs of 75 questions in 60 minutes.

Content outlines, fees and passing standards change; this guide follows the materials listed under Verification as of October 2026. Check the licensing authority and test administrator before you register.