ABA Emissions Control & Environmental Compliance 3 — Questions and Answers
Question 1: OSHA's permissible exposure limit (PEL) for occupational noise over an 8-hour workday is:
- 85 dBA
- 90 dBA (Correct answer)
- 95 dBA
- 100 dBA
Correct answer: 90 dBA
OSHA sets the 8-hour TWA PEL at 90 dBA using a 5 dB exchange rate; exposures at or above this level require engineering or administrative controls.
Question 2: Under OSHA's Hearing Conservation Amendment, employers must implement a hearing conservation program when worker noise exposure reaches or exceeds a TWA of:
- 80 dBA
- 85 dBA (Correct answer)
- 90 dBA
- 95 dBA
Correct answer: 85 dBA
The OSHA action level is 85 dBA TWA; at this level employers must provide audiometric testing, hearing protection devices, and training even though it is below the PEL.
Question 3: OSHA defines a standard threshold shift (STS) as an average shift of how many dB at 2000, 3000, and 4000 Hz compared to the baseline audiogram?
- 5 dB
- 10 dB (Correct answer)
- 15 dB
- 20 dB
Correct answer: 10 dB
An STS is a 10 dB or greater average change in hearing threshold at 2000, 3000, and 4000 Hz, which triggers re-evaluation and enhanced hearing protection.
Question 4: Under OSHA 29 CFR 1910.95, a baseline audiogram must be obtained within how many months of a new employee's enrollment in the hearing conservation program?
- 1 month
- 3 months
- 6 months (Correct answer)
- 12 months
Correct answer: 6 months
OSHA allows up to 6 months for the baseline audiogram, provided the employee wears hearing protection devices during that interim period.
Question 5: According to OSHA, audiometric testing in a hearing conservation program must be performed by or under the supervision of a:
- Licensed occupational therapist
- Licensed or certified audiologist, otolaryngologist, or physician (Correct answer)
- OSHA-certified noise control technician
- Any trained company safety officer holding OSHA-10 certification
Correct answer: Licensed or certified audiologist, otolaryngologist, or physician
OSHA requires occupational audiograms to be conducted by or under the direct supervision of an audiologist, otolaryngologist, or physician.
Question 6: NIOSH's recommended exposure limit (REL) for occupational noise differs from OSHA's PEL primarily in that NIOSH recommends:
- 85 dBA with a 5 dB exchange rate
- 85 dBA with a 3 dB exchange rate (Correct answer)
- 90 dBA with a 3 dB exchange rate
- 80 dBA with a 5 dB exchange rate
Correct answer: 85 dBA with a 3 dB exchange rate
NIOSH recommends 85 dBA REL using the 3 dB equal-energy exchange rate, which is more protective than OSHA's 90 dBA PEL with a 5 dB exchange rate.
Question 7: OSHA requires employers to notify workers in writing of a confirmed persistent standard threshold shift within:
- 7 days of confirming the shift
- 21 days of confirming the shift (Correct answer)
- 30 days of confirming the shift
- 60 days of the annual audiogram date
Correct answer: 21 days of confirming the shift
OSHA mandates that workers be notified in writing within 21 days of a confirmed STS determination, and HPD adequacy must be re-evaluated.
ABA Emissions Control & Environmental Compliance 3
OSHA's permissible exposure limit (PEL) for occupational noise over an 8-hour workday is: