CAOHC Audiometric Testing Procedures 2 — Questions and Answers
Question 1: What is the maximum permissible ambient noise level in an audiometric test booth at 1000 Hz according to OSHA?
- 40 dB SPL (Correct answer)
- 25 dB SPL
- 50 dB SPL
- 15 dB SPL
Correct answer: 40 dB SPL
OSHA specifies maximum permissible ambient noise levels for audiometric test rooms, with 40 dB SPL at 1000 Hz per Appendix D of 29 CFR 1910.95.
Appendix D of 29 CFR 1910.95 establishes maximum ambient noise levels for audiometric test rooms. These levels ensure that background noise does not mask test tones and cause falsely elevated thresholds.
Question 2: During pure-tone audiometry, what is the standard procedure when a patient does not respond at the initial presentation level?
- Increase the intensity in 5 dB steps until a response is obtained (Correct answer)
- Immediately retest at the same level three more times
- Switch to the opposite ear and begin testing
- Record no response and move to the next frequency
Correct answer: Increase the intensity in 5 dB steps until a response is obtained
Standard audiometric procedure calls for increasing intensity in 5 dB steps when no response is obtained, then decreasing in 10 dB steps after a response.
The modified Hughson-Westlake procedure uses a down 10, up 5 bracketing technique. Threshold is defined as the lowest level at which the patient responds at least 50% of the time.
Question 3: Which ear should typically be tested first during audiometric evaluation?
- The better-hearing ear as reported by the patient (Correct answer)
- Always the right ear first
- Always the left ear first
- The ear with the most noise exposure history
Correct answer: The better-hearing ear as reported by the patient
Standard practice is to begin testing with the better ear as reported by the patient, which helps establish cooperation and understanding of the test procedure.
Beginning with the better-hearing ear familiarizes the patient with the test tones and response procedure when signals are most easily heard. If the patient reports no difference, conventional practice starts with the right ear.
Question 4: What is the standard test frequency sequence in occupational audiometry?
- 1000, 2000, 3000, 4000, 6000, 8000, then 500 Hz, with a retest at 1000 Hz (Correct answer)
- 500, 1000, 2000, 3000, 4000, 6000, 8000 Hz sequentially
- 8000, 6000, 4000, 3000, 2000, 1000, 500 Hz descending
- Only 2000, 3000, and 4000 Hz for STS monitoring
Correct answer: 1000, 2000, 3000, 4000, 6000, 8000, then 500 Hz, with a retest at 1000 Hz
The standard sequence starts at 1000 Hz as a familiarization frequency, proceeds through high frequencies, drops to 500 Hz, then retests 1000 Hz to verify reliability.
Testing begins at 1000 Hz because it is easily audible and serves as a training frequency. The 1000 Hz retest serves as a reliability check; if the retest differs by more than 5 dB, the entire ear must be retested.
Question 5: What type of transducer is most commonly used for standard occupational audiometry?
- Supra-aural headphones such as TDH-39 or equivalent (Correct answer)
- Insert earphones exclusively
- Bone conduction oscillators
- Free-field speakers
Correct answer: Supra-aural headphones such as TDH-39 or equivalent
Supra-aural headphones such as the TDH-39 or TDH-49 are the traditional standard transducers for occupational audiometry.
Supra-aural headphones have been the standard for occupational audiometry and are referenced in OSHA calibration requirements. Insert earphones offer advantages including reduced ambient noise interference and elimination of ear canal collapse artifacts.
Question 6: How often must an audiometer undergo an exhaustive calibration check?
- At least annually for acoustic calibration (Correct answer)
- Daily before each testing session
- Every 5 years by the manufacturer
- Only when functional checks indicate a problem
Correct answer: At least annually for acoustic calibration
OSHA requires that audiometers receive an acoustic calibration at least annually, in addition to daily functional checks.
Audiometers require three levels of calibration maintenance: daily functional checks, annual acoustic calibration per ANSI S3.6 standards, and exhaustive electroacoustic calibration every 2 years or when needed.
CAOHC Audiometric Testing Procedures 2
What is the maximum permissible ambient noise level in an audiometric test booth at 1000 Hz according to OSHA?