Free CAOHC Audiometric Booth and Equipment Calibration Questions and Answers 1 — Questions and Answers
Question 1: What is the maximum permissible ambient noise level for the 500 Hz octave band in an audiometric test room according to ANSI S3.1?
- 40 dB SPL (Correct answer)
- 50 dB SPL
- 25 dB SPL
- 60 dB SPL
Correct answer: 40 dB SPL
ANSI S3.1 specifies maximum permissible ambient noise levels (MPANLs) for audiometric testing rooms. For the 500 Hz octave band, the MPANL is 40 dB SPL when testing to 0 dB HL using supra-aural earphones.
Question 2: How often must audiometers used in occupational hearing conservation programs receive exhaustive calibration?
- At least annually (Correct answer)
- Every 5 years
- Only when purchased new
- Monthly
Correct answer: At least annually
OSHA requires exhaustive (electroacoustic) calibration of audiometers at least annually. This comprehensive calibration verifies that the audiometer's output meets ANSI specifications across all frequencies and intensity levels.
Question 3: What is the purpose of the daily biological calibration check of an audiometer?
- To verify the audiometer is functioning within acceptable limits by testing a person with known, stable hearing (Correct answer)
- To calibrate the audiometer to a specific worker's hearing levels
- To replace the need for annual electroacoustic calibration
- To test the audiometric booth's noise isolation
Correct answer: To verify the audiometer is functioning within acceptable limits by testing a person with known, stable hearing
Daily biological calibration involves testing a person with known, stable hearing thresholds. If results deviate by more than 10 dB from established levels at any frequency, the audiometer requires service before being used for testing.
Question 4: What is the maximum allowable deviation from reference values during a daily functional check of an audiometer?
- Plus or minus 10 dB at any test frequency (Correct answer)
- Plus or minus 5 dB at any test frequency
- Plus or minus 15 dB at any test frequency
- Plus or minus 20 dB across all frequencies combined
Correct answer: Plus or minus 10 dB at any test frequency
During a daily functional (biological) check, audiometer output should not deviate by more than plus or minus 10 dB from established reference values at any test frequency. Deviations beyond this indicate the need for recalibration or service.
Question 5: Which ANSI standard governs the specifications for audiometers used in hearing conservation programs?
- ANSI S3.6 (Correct answer)
- ANSI S3.1
- ANSI S1.4
- ANSI S12.6
Correct answer: ANSI S3.6
ANSI S3.6 specifies the requirements for audiometric equipment, including output levels, frequency accuracy, and harmonic distortion limits. Audiometers used in occupational programs must meet this standard.
Question 6: What is the primary purpose of an audiometric test booth?
- To reduce ambient noise to levels that allow valid hearing threshold measurements (Correct answer)
- To amplify the audiometric test signals
- To provide privacy for the worker during testing only
- To eliminate the need for calibrated audiometers
Correct answer: To reduce ambient noise to levels that allow valid hearing threshold measurements
The audiometric booth provides a controlled acoustic environment with reduced ambient noise. Without adequate noise reduction, background noise can mask test signals and result in falsely elevated hearing thresholds.
Free CAOHC Audiometric Booth and Equipment Calibration Questions and Answers 1
What is the maximum permissible ambient noise level for the 500 Hz octave band in an audiometric test room according to ANSI S3.1?