OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

February 25, 2026

Mr. Johnathan Stutzman
ATO EOSH Services,
AJW-232 Program Manager
Federal Aviation Administration
800 Independence Ave., 7W-333
Washington DC 20591

Dear Mr. Stutzman:

Thank you for your inquiry to the Occupational Safety and Health Administration's (OSHA) E-Correspondence webpage. After a member of my staff contacted you to explain that OSHA does not have any publication that fully answers your question, you requested that OSHA issue an official interpretation. You requested information regarding OSHA's Occupational Noise Exposure standard (Noise standard), 29 CFR § 1910.95. Your question specifically relates to the use of bone conduction audiometric testing (audiogram). This letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any questions not delineated within your original correspondence. Your scenario and specific questions are paraphrased below, followed by OSHA's response.

Background: In your correspondence, you state that to comply with paragraph 1910.95(g) of OSHA's noise standard, employers must provide audiometric testing to employees exposed to hazardous noise at or above the action level. According to paragraph 1910.95(h), audiometric tests shall be pure tone, air conduction, to conduct threshold shift comparisons. You also state there are employees with health issues that preclude the accurate use of pure tone audiometry. This includes employees with tinnitus (unable to hear the pure tones), and paragraph 1910.95(h)(3) permits pulsed-tone audiometry to be used in these cases. However, neither of these types of audiometry may be effective for employees with more severe hearing loss, such as employees that use implanted and non-removable hearing devices; employees with severe hearing loss in the 2,000 Hz, 3,000 Hz, and 4,000 Hz range (unable to hear sounds below 70 dB); or employees with profound hearing loss (unable to hear sounds below 95 dB).

Question 1: Can employers conduct audiograms and threshold comparisons with bone conduction audiometry in lieu of the pure tone or pulsed-tone audiometry for employees with severe hearing loss?

Response: No. OSHA's noise standard does not permit the substitution of bone conduction audiometry for pure or pulse-tone air conduction audiometric testing. Section 1910.95(h)(1) states that, “Audiometric testing shall be pure tone, air conduction, hearing threshold examinations, with frequencies including as a minimum 500, 1000, 2000, 3000, 4000, and 6000 Hz. Tests at each frequency shall be taken separately for each ear.” Section 1910.95(h)(3) goes on to provide that, if pulse-tone audiometers are used, they must meet the requirements specified in mandatory Appendix C of the OSHA noise standard, Audiometric Measuring Instruments.

The OSHA noise standard requires certain functions of the audiometric testing program be performed by a licensed or certified audiologist, otolaryngologist, or other physician. For example, these professionals are responsible for reviewing the validity of audiograms, making determinations as to whether a hearing loss is work-related, and determining the need to refer employees for further audiological evaluation. Specifically, Section 1910.95(g)(7)(iii) provides that the audiologist, otolaryngologist, or physician must review problem audiograms and determine whether there is a need for further evaluation. For purposes of OSHA's noise standard, when pure or pulsed-tone, air-conduction, audiometric test results cannot be accurately measured or obtained, the audiogram is considered a “problem audiogram.” In such cases, the audiologist, otolaryngologist, or physician may refer the employee for further audiological evaluation and testing. In addition, the standard allows these professionals to determine the need for employee referral for further testing when test results are questionable or when problems of a medical nature are suspected. See, the preamble to OSHA's March 8, 1983, final rule, Occupational Noise Exposure, Hearing Conservation amendment, 48 Federal Register 9738 at 9758.

Question 2: How is a threshold shift comparison conducted or reported for these employees if values in the 2,000 Hz, 3,000 Hz, and 4,000 Hz are unable to be obtained?

Response: If hearing levels at 2,000 Hz, 3,000 Hz and 4,000 Hz cannot be obtained with an air-conduction audiogram, the results should be documented accordingly, for example “no response” or “unable to record threshold” at the affected frequencies. Again, these cases are considered a problem audiogram that must be reviewed by an audiologist, otolaryngologist, or physician to determine if referral for further evaluation or testing is needed. The preamble to OSHA's 1983 final rule notes that these hearing professionals have extensive education and training in audiometry and the recognition of various types of hearing loss. See, 48 Federal Register at 9758. As such, these hearing professionals can determine when alternative tests or protocols are required to obtain valid baseline audiograms and conduct annual hearing tests to determine if hearing loss is worsening due to occupational noise exposure. Please be aware that when alternate audiometric testing methods are used, they may be repeated to meet the annual hearing evaluation requirement for any employee where a determination was made and documentation is maintained from an audiologist, otolaryngologist, or physician stating that hearing levels cannot be obtained with an air conduction audiogram. In addition, any identified work-related threshold shift that meets the criteria in OSHA's injury and illness recordkeeping regulation at 29 CFR 1904.10 must be recorded on the OSHA Form 300, Log of Work-Related Injuries and Illnesses. Also please be aware of the occlusion effect when using bone conducting testing.1

Furthermore, exposure to workplace noise above the OSHA permissible exposure limit may worsen residual hearing. As such, hearing professionals should also advise the employer and the hearing-impaired worker on how to protect the worker's hearing, such as the type(s) and correct use of hearing protectors recommended, and whether workers should limit or avoid noise exposure to prevent worsening hearing loss. In addition, the hearing professional may conduct testing to assess functional hearing (e.g., word recognition and speech in noise testing) and make recommendations regarding hearing in safety sensitive positions where workers must be able to understand speech in noisy environments and hear warning signals.

Additional information that may be helpful include OSHA's Safety and Health Information Bulletins (SHIBs) discussing hearing conservation and accommodations for hearing-impaired workers: Hearing Conservation for the Hearing-Impaired Worker2 and Innovative Workplace Safety Accommodations for Hearing-Impaired Workers3. The Corbitt letter of interpretation (June 11, 2025) that discusses audiometric testing for persons with cochlear implants may also be helpful.4

Thank you for your interest in occupational safety and health. I hope you find this information helpful. OSHA's requirements are set by statute, standards, and regulations. Letters of interpretation do not create new or additional requirements but rather explain these requirements and how they apply to particular circumstances. This letter constitutes OSHA's interpretation of the requirements discussed. From time to time, letters are affected when the agency updates a standard, a legal decision impacts a standard, or changes in technology affect the interpretation. To ensure that you are using the correct information and guidance, please consult OSHA's website at www.osha.gov. If you have further questions, please feel free to contact the Office of Health Enforcement at (202) 693-2190.

Sincerely,

Erin P. Gilmore, Acting Director
Directorate of Enforcement Programs

1 https://www.thieme-connect.com/products/ejournals/pdf/10.3766/jaaa.17045.pdf
2 https://www.osha.gov/sites/default/files/publications/shib122705.pdf
3 https://www.osha.gov/sites/default/files/publications/shib072205.pdf
4 https://www.osha.gov/laws-regs/standardinterpretations/2025-06-11