CAOHC OSHA Noise Standard Compliance 2 — Questions and Answers
Question 1: What is OSHA's position on the use of cotton or tissue plugs as hearing protectors?
- They are not acceptable hearing protectors because they provide inadequate and unpredictable attenuation (Correct answer)
- They are acceptable for noise levels below 95 dBA
- OSHA considers them equivalent to foam earplugs
- They are acceptable if the employer provides them at no cost
Correct answer: They are not acceptable hearing protectors because they provide inadequate and unpredictable attenuation
Cotton, tissue, and similar improvised ear plugs are not acceptable hearing protectors under OSHA. They provide minimal and inconsistent attenuation that does not reliably protect against hazardous noise levels.
Question 2: Under OSHA, how must noise measurement instruments be calibrated?
- Before and after each measurement session using an acoustic calibrator traceable to national standards (Correct answer)
- Only once per year during the annual audiometer calibration
- Calibration is not required for noise measurement instruments
- Only when the instrument displays an error message
Correct answer: Before and after each measurement session using an acoustic calibrator traceable to national standards
OSHA requires that noise measurement instruments (sound level meters and dosimeters) be calibrated before and after each measurement session. The calibrator must be traceable to national standards to ensure measurement accuracy.
Question 3: What is the OSHA provision regarding workers who are temporarily absent from the hearing conservation program?
- Workers returning from absence must receive a new annual audiogram and updated training before resuming noise-exposed duties (Correct answer)
- Workers on leave are permanently removed from the program
- No re-entry procedures are required regardless of absence duration
- Workers must complete an entirely new baseline audiogram after any absence
Correct answer: Workers returning from absence must receive a new annual audiogram and updated training before resuming noise-exposed duties
Workers returning from extended absence should receive an updated annual audiogram and training. While OSHA does not specify exact re-entry procedures, best practice ensures returning workers have current audiometric records and training before noise exposure resumes.
Question 4: What does OSHA require regarding the fit and effectiveness of hearing protectors provided to workers?
- Employers must ensure protectors are properly fitted and workers are trained in their correct use (Correct answer)
- Simply providing protectors satisfies the requirement regardless of fit
- Only custom-molded protectors satisfy OSHA requirements
- Workers must be fit-tested annually with documented results
Correct answer: Employers must ensure protectors are properly fitted and workers are trained in their correct use
OSHA requires that employers ensure hearing protectors fit properly and that workers are trained in correct insertion and use. A protector that is not properly fitted provides significantly less protection than its rated NRR suggests.
Question 5: Which A-weighting scale does OSHA require for noise measurements, and why?
- A-weighting because it approximates the human ear's frequency response at moderate sound levels (Correct answer)
- C-weighting because it captures all frequencies equally
- Z-weighting because it provides the flattest frequency response
- No specific weighting is required by OSHA
Correct answer: A-weighting because it approximates the human ear's frequency response at moderate sound levels
OSHA requires A-weighted noise measurements (dBA) because the A-weighting filter approximates the frequency sensitivity of the human ear at moderate sound levels. This provides measurements that correlate with the hearing damage risk from noise exposure.
Question 6: What is the significance of the 'criterion level' in OSHA noise dosimetry?
- It is the constant noise level (90 dBA) that produces a 100% dose over the criterion duration (8 hours) (Correct answer)
- It is the quietest noise level that can be measured
- It is the noise level that causes immediate hearing loss
- It is the ambient noise level required in the audiometric booth
Correct answer: It is the constant noise level (90 dBA) that produces a 100% dose over the criterion duration (8 hours)
The criterion level (90 dBA) is the constant noise level that, if maintained for the criterion duration (8 hours), results in a 100% noise dose — exactly at the OSHA PEL. This is the reference point for all dose calculations.
CAOHC OSHA Noise Standard Compliance 2
What is OSHA's position on the use of cotton or tissue plugs as hearing protectors?