OSHA 1910.95 Appendix F contains age correction tables that employers may use when determining whether a standard threshold shift (STS) has occurred. Age correction subtracts expected age-related hearing changes (presbycusis) from the measured audiometric shift, potentially reducing the number of STS determinations and OSHA 300 Log recordable cases. According to the CDC, approximately 22 million U.S. workers are exposed to hazardous occupational noise annually — and for many of them, especially workers over 40, age-related threshold changes can account for a meaningful portion of measured audiometric shift. This guide explains how Appendix F age correction works, when to use it, and how to apply it correctly.
What Age Correction Is and Why It Exists
As people age, hearing thresholds naturally worsen — a process called presbycusis. This age-related hearing change is independent of noise exposure and occurs even in populations with minimal noise history. For workers enrolled in a hearing conservation program, this creates a problem: when annual audiograms show threshold changes compared to the baseline, some portion of that change may reflect normal aging rather than occupational noise exposure.
OSHA Appendix F addresses this by providing age correction tables — expected threshold changes at 2,000, 3,000, and 4,000 Hz based on the worker’s sex and the number of years elapsed between the baseline audiogram and the current annual audiogram. Subtracting these expected values from the measured shift produces an age-corrected shift that theoretically represents the noise-induced component alone.
When Age Correction Applies (and When It’s Worth Using)
Age correction is optional — OSHA does not require it. Employers may apply it or not. The practical question is: does age correction change the STS determination? If the measured average shift is 14 dB and age correction reduces it to 8 dB, applying correction avoids an STS determination, 21-day notification, HPD review, and potential 300 Log entry. If the measured shift is 6 dB before and after correction, there’s no STS either way and age correction makes no difference.
Age correction is most impactful for workers in their 40s and 50s, where presbycusis at 3,000 and 4,000 Hz accelerates. For workers under 35, the expected changes are small and rarely affect the STS determination.
How to Apply Appendix F Age Correction: Step by Step
- Record the worker’s age at baseline and their age at the current annual audiogram.
- Look up Appendix F values for the worker’s sex at each of the three frequencies (2,000, 3,000, 4,000 Hz), for the age at baseline and for the age at the current test. Calculate the difference (the expected change over the interval).
- Subtract the age correction value from the measured threshold shift at each frequency. If the age correction value exceeds the measured shift at a frequency, use zero (not a negative number) for that frequency.
- Average the three age-corrected shifts and compare to the 10 dB STS threshold.
If the age correction value at any frequency is larger than the measured shift, the age-corrected shift at that frequency is set to zero — not a negative number. This prevents age correction from creating the appearance of improved hearing beyond what was measured. The averaging is then performed on the zero-floored values.
Interactive Age Correction Calculator
Enter the worker’s details and audiogram thresholds. The calculator applies Appendix F age correction to determine whether the age-corrected shift still constitutes an STS.
Age correction values from OSHA 1910.95 Appendix F. Results are for educational reference; all STS determinations should be reviewed by a qualified professional supervisor. The professional supervisor’s determination governs.
Age Correction and OSHA 300 Log Recordability
Age correction may also be applied before the 29 CFR 1904.10 recordability determination. OSHA’s hearing loss recordkeeping rule allows employers to use age correction to determine whether a case is recordable. If age correction eliminates the STS, the case is not recordable. If age correction reduces the STS but the remaining threshold average still meets the 25 dB HL recordability criterion, the case remains recordable. Document whether age correction was applied and the result of both the raw and age-corrected calculations.
The DoD Contrast: DoDI 6055.12 Prohibits Age Correction
DoD DoDI 6055.12 explicitly prohibits age correction in STS determinations for military personnel. Every audiometric shift is compared to the unadjusted baseline regardless of the service member’s age. This produces a higher rate of STS determinations than OSHA programs that apply age correction, reflecting the DoD’s operational readiness priority over administrative convenience. Defense contractors working on DoD sites should be aware of this distinction when managing programs for mixed populations.
Frequently Asked Questions
No. Age correction under OSHA 1910.95 Appendix F is optional. Employers may apply it or not. If applying age correction would reduce the measured STS to below the 10 dB threshold, the employer may use the age-corrected value to determine that no STS occurred. Document whether age correction was applied in the worker’s audiometric record.
Age correction may also be applied before the OSHA 300 Log recordability determination under 29 CFR 1904.10. If age correction eliminates the STS, the case is not recordable. If age correction reduces the STS but the remaining threshold still meets recordability criteria, the case remains recordable.
No. DoDI 6055.12 explicitly prohibits age correction for STS determinations for military personnel. Every shift is compared to the unadjusted baseline. This produces more STS determinations than OSHA programs that routinely apply Appendix F correction, reflecting the DoD’s operational readiness priority.
Automated STS calculation with age correction built in
Soundtrace calculates both raw and age-corrected STS for every annual audiogram, routes determinations to the professional supervisor, and documents the calculation method — so your age correction decisions are always auditable.
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