FRA vs. OSHA Hearing Conservation: A Side-by-Side Guide

Employers operating in the general railroad system of transportation are regulated under the Federal Railroad Administration’s occupational noise standard (49 CFR Part 227, Subpart B) rather than OSHA’s hearing conservation standard (29 CFR 1910.95). The two frameworks share a common origin, since FRA’s rule was written to closely track OSHA’s, but several provisions diverge in ways that matter for how you build and document a program.

Two rules, one lineage

FRA’s occupational noise rule and OSHA’s hearing conservation standard descend from the same regulatory family. The action level, the permissible exposure limit, the 5 dB exchange rate, the standard threshold shift math, and the age-correction tables are the same in both. FRA’s Appendix C to Part 227 explicitly notes that OSHA and FRA use the same STS definition and the same NIOSH-derived age corrections.

The divergence is procedural, not clinical. It shows up in how often a hearing test actually has to happen, how quickly an employee must be told about a shift, what edition of the audiometer standard applies, and which paperwork trail proves compliance. For a program manager, that means most of your clinical protocol carries over unchanged, while your scheduling and recordkeeping rules need FRA-specific handling.

Where FRA and OSHA are identical

Before the differences, it helps to see how much is genuinely the same. Building a program to these shared elements satisfies both agencies:

• Action level: 85 dB(A) 8-hour TWA under both § 1910.95(c) and FRA’s § 227.5 definitions.
• Permissible exposure limit: 90 dB(A) 8-hour TWA equivalent with a 5 dB exchange rate under both.
• Baseline audiogram: within 6 months of first exposure or first tour of duty, extendable to 12 months when a mobile test van is used, with hearing protectors required in the interim.
• Quiet period before baseline: 14 hours without occupational noise above the action level, with protectors permitted as a substitute.
• STS definition: a 10 dB average shift at 2000, 3000, and 4000 Hz in either ear, relative to baseline.
• Age correction: optional, using identical NIOSH-derived tables.
• HPD attenuation target after STS: reduce exposure to 85 dB(A) TWA or lower under both.

The audiology is shared. What changes between FRA and OSHA is the calendar and the file cabinet, not the audiogram.

The provision that matters most: testing cadence

The single largest substantive gap between the two frameworks is in 49 CFR 227.109(f). FRA splits the annual audiogram into two separate obligations that sit on different parties.

1. The railroad must offer an audiometric test every calendar year, with the offer date falling within a 280 to 450 day window of the prior year’s offer.
2. The employee is only required to complete a test at least once every 1,095 days (three years). An employee can decline the annual offer twice in a row without creating a compliance problem for the railroad.

OSHA’s § 1910.95(g)(6) contains no equivalent opt-out. The annual audiogram is a flat requirement with no employee discretion built in. This is the central divergence: under FRA, a worker can legally go up to three years between completed audiograms, while under OSHA every enrolled worker is tested every year.

The same offer-and-complete structure repeats for training. FRA’s § 227.119 requires the railroad to offer training annually within the same 280 to 450 day window, while the employee must complete training at least once every 1,095 days. OSHA’s § 1910.95(k) requires annual completion with no opt-out. So the three-year completion floor is a pattern across FRA, not a quirk isolated to audiograms.

STS definition and notification timing

The way you identify a standard threshold shift is identical between the agencies: the same 10 dB average shift at 2000, 3000, and 4000 Hz, the same optional age correction. Where they differ is the clock that starts once you have made the determination.

• OSHA: written notice to the employee within 21 days of the determination, under § 1910.95(g)(8).
• FRA: written notice within 30 days of the determination, under § 227.109(h)(1).

The substantive follow-up steps are the same under both rules: refit and retrain on hearing protection, and refer for a clinical audiological or otological evaluation when non-HPD-related pathology is suspected. FRA also codifies a more detailed, appendix-level baseline revision methodology in Appendix C, with separate rules for persistent improvement and persistent STS, each ear evaluated independently. OSHA’s revision approach is less granular in the regulatory text itself.

Test room and audiometer requirements

The physical test environment and equipment requirements line up closely, with FRA citing a specific audiometer edition and adding a mobile-van calibration cycle.

Test room ambient noise

Both agencies publish octave-band sound pressure level limits for the audiometric test room: Appendix D to Part 227 for FRA and Appendix D to 1910.95 for OSHA. The tables are functionally identical, covering both supra-aural and insert earphone configurations. These limits align with ANSI S3.1, the consensus standard for maximum permissible ambient noise levels in audiometric test rooms. If your test space meets ANSI S3.1 for the transducer type in use, it meets the Appendix D limits under both frameworks.

Audiometer standard and calibration

FRA incorporates ANSI S3.6-2004 specifically by reference in § 227.111(b), while OSHA’s Appendix C uses more flexible edition language (ANSI S3.6-2004 or later editions are generally accepted). Calibration cadence is otherwise shared: a functional check before each day’s use, an acoustic calibration annually, and an exhaustive calibration every 2 years. FRA adds one wrinkle in § 227.111(d)(3): mobile-van audiometers require the exhaustive calibration annually rather than every 2 years.

Who may administer the test

This is an area where FRA and OSHA are more alike than different. Both frameworks are built on the same two-tier structure: a trained technician actually runs the audiogram, working under a professional supervisor who must be drawn from the same three professions, an audiologist, otolaryngologist, or physician. If you already staff an OSHA program correctly, you have the core of an FRA-compliant staffing model in place. The differences are largely in labeling, plus one added certification option.

• OSHA § 1910.95(g)(3): a certified audiometric technician who is responsible to a professional supervisor, or an audiologist, otolaryngologist, or physician conducting the test directly.
• FRA §§ 227.5 and 227.109(c): a Qualified Technician working under a Professional Supervisor of the Audiometric Monitoring Program, who must be an audiologist, otolaryngologist, or physician, the same professional pool OSHA names.

The one substantive addition on the FRA side is how a technician becomes “qualified.” The technician may be certified by CAOHC or certified directly by the Professional Supervisor of the Audiometric Monitoring Program. In other words, CAOHC certification is one route, but it is not the only route: the Professional Supervisor can certify a technician in-house. That flexibility matters for railroads building an internal program, because a qualified technician can be developed and certified under the direct oversight of your program’s audiologist or physician rather than requiring every tester to hold a CAOHC card. OSHA relies on the same professional-supervision principle; FRA simply writes the alternative certification path into the rule.

Recordkeeping and reporting

Recordkeeping is where FRA and OSHA route through different systems, even when the underlying retention periods end up comparable.

The practical takeaway is that an FRA program cannot simply reuse OSHA 300-log habits. FRA maintains a standalone STS record with its own 5-year retention period, and it reports occupational injury and illness through the FRA reporting system rather than the OSHA 300 log. These are separate vehicles, not cross-filed.

OSHA vs. FRA at a glance: comparison matrix

This matrix consolidates the reference points above into a single side-by-side recap. The final column gives a plain-language verdict for each element, whether it carries over unchanged, needs FRA-specific handling, or is broadly shared with a few wrinkles, along with why that distinction matters when you build a program. Citations point to the controlling section in each rulebook.

Read the verdict column top to bottom and the pattern is hard to miss: the clinical elements, exposure math, STS math, test protocol, and staffing model, are shared, while the calendar and the paperwork are where FRA needs its own handling.

What this means for program design

A program built to OSHA’s annual-mandatory cadence exceeds FRA’s floor rather than falling short of it. Testing every employee every year, instead of allowing a three-year gap, means earlier detection of a standard threshold shift for any worker who would otherwise have exercised the FRA opt-out.

That said, frequency alone does not satisfy FRA’s separate recordkeeping requirements. To be defensibly FRA compliant, a railroad running an OSHA-style annual program should still:

• Document the annual test and training offer for each employee, dated within the 280 to 450 day window, whether or not the employee accepts.
• Maintain a standalone STS record per § 227.121(f) with the required fields, retained 5 years, separate from injury logs.
• Confirm audiometers meet ANSI S3.6-2004 specifically, and shorten mobile-van exhaustive calibration to annual.
• Verify test rooms meet the Appendix D octave-band limits, aligned with ANSI S3.1, for the transducer type in use.
• Route STS notifications within FRA’s 30-day window and injury reporting through FRA Form F 6180.55a rather than the OSHA 300 log.

Testing more often than FRA requires is the easy part. The compliance risk for railroads sits in the offer documentation and the standalone STS record, not in how frequently the audiogram happens.

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