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Audiometric testing is the only way to know whether your hearing conservation program is actually protecting workers' hearing -- or just going through the motions. OSHA requires it for a reason: it provides objective, quantified evidence of whether noise-exposed employees are experiencing hearing threshold changes over time, and it triggers specific employer obligations when those changes meet the Standard Threshold Shift threshold. This complete guide covers everything industrial employers need to know about audiometric testing in 2025: what it is, who needs it, how to run it, what the results mean, and how modern in-house testing has transformed program efficiency.
OSHA 1910.95(g) requires audiometric testing -- at no cost to employees -- for all workers exposed at or above 85 dBA TWA. Every covered worker needs a baseline audiogram (within 6 months of first exposure) and an annual audiogram (every 12 months thereafter). Standard Threshold Shifts must be identified and acted upon within 21 days.
Audiometric testing in the industrial context is pure-tone air conduction hearing testing -- the same fundamental test used by audiologists in clinical settings, adapted for the occupational health environment. The worker listens through headphones and responds each time they detect a tone. The softest detectable level at each frequency is recorded as the hearing threshold, and those thresholds are plotted on an audiogram.
In a hearing conservation program, the audiogram serves as a medical record of the worker's hearing function over time. The baseline audiogram establishes the starting reference. Each annual audiogram is compared to the baseline to detect changes. Sustained changes that meet OSHA's definition of a Standard Threshold Shift trigger specific employer obligations.
Under OSHA 1910.95(g), audiometric testing must be provided to all employees whose noise exposure equals or exceeds the action level of 85 dBA TWA (8-hour time-weighted average). This is not optional for the employer, and it must be provided at no cost to the employee.
| Noise Exposure Level | Audiometric Testing Required? | Notes |
|---|---|---|
| Below 85 dBA TWA | Not required by 1910.95 | OSHA hearing conservation requirements do not apply below action level |
| At or above 85 dBA TWA (action level) | Yes -- baseline + annual | Full hearing conservation program triggered; testing at no cost to employee |
| At or above 90 dBA TWA (PEL) | Yes -- same requirements | Additional HPD use obligation and engineering control requirements also apply |
| Employees with a confirmed STS | Yes -- continue annual testing | May also require re-test within 30 days and upgraded HPDs |
The employer must first conduct noise monitoring to determine which employees are at or above the action level. There is no substitute for actual measurement -- assuming who is or is not covered based on job title or proximity to equipment is not compliant.
The baseline audiogram establishes the reference hearing level against which all future annual tests will be compared. OSHA requires it to be completed within 6 months of the employee's first noise exposure at or above the action level. If mobile testing is the primary method used, this window extends to 12 months -- but hearing protection must be worn during the interim period.
The baseline should ideally be conducted after a period of at least 14 hours away from hazardous noise, to avoid temporary threshold shifts affecting the reference measurement. Employees should be informed of this requirement in advance.
Annual audiograms must be conducted at least once every 12 months for every covered employee. Each annual result is compared to the baseline to identify Standard Threshold Shifts. The 12-month clock runs from the baseline (or from the prior annual test) -- lapsed testing is one of the most commonly cited 1910.95 violations.
When an annual audiogram reveals a potential STS, OSHA recommends (and many programs require) a retest within 30 days to distinguish a genuine persistent shift from a temporary threshold shift caused by recent noise exposure before the test. If the retest confirms the STS, the employer must act.
OSHA specifies technical standards for audiometric testing equipment and testing conditions. These are not discretionary -- using non-compliant equipment or testing in an environment with too much background noise invalidates the results and exposes the employer to citation.
| Requirement | OSHA Specification |
|---|---|
| Audiometer type | Pure tone, air conduction audiometer meeting ANSI S3.6 specifications |
| Frequencies tested | Minimum 500, 1000, 2000, 3000, 4000, and 6000 Hz per ear |
| Audiometer calibration | Biological check (daily), acoustic calibration (annually), exhaustive calibration (every 2 years or after repair) |
| Testing environment | Background noise levels must not exceed the maximum allowable levels in OSHA Appendix D (e.g., max 40 dB at 500 Hz, max 37 dB at 1000 Hz for standard audiometry) |
| Audiometric booth | Required or equivalent quiet environment must be verified by measurement |
Audiometric testing conducted with an improperly calibrated audiometer produces unreliable results -- and if OSHA requests calibration records during an inspection and they are absent or show missed calibration windows, the entire testing program may be considered non-compliant. Maintain calibration logs as rigorously as audiometric test records.
OSHA specifies who is qualified to perform and supervise industrial audiometric testing under 1910.95(g)(3):
In most industrial programs, day-to-day testing is conducted by an Occupational Hearing Conservationist (OHC) -- a CAOHC-certified technician -- with physician or audiologist oversight for review of results, STS determinations, and referrals. This is the model Soundtrace uses: in-house testing by OHC-certified staff or automated audiometers, with professional audiology oversight built into the platform.
Each audiogram produces a threshold measurement at six frequencies per ear. Most results fall into three categories for program purposes:
A Standard Threshold Shift is a change in hearing threshold relative to the baseline of an average of 10 dB or more at 2000, 3000, and 4000 Hz in either ear. When an STS is detected, OSHA requires:
Under OSHA 1910.95(m), audiometric test records must be retained for the duration of the affected employee's employment. This is a longer retention requirement than most OSHA records -- it effectively means you keep audiometric records for a worker's entire career with your organization. Each record must include:
Paper audiogram records are still technically compliant but create significant operational risk -- they can be lost, damaged, or inaccessible when needed. Digital platforms that store all audiometric records, calibration logs, and STS calculations in a searchable database eliminate this risk entirely and make OSHA inspection responses straightforward.
| Method | How It Works | Pros | Cons |
|---|---|---|---|
| Mobile audiometric van | Third-party van comes to the facility once a year; employees file through for testing | No facility investment; handled externally | Scheduling disruption; long queues; limited flexibility; annual visit only; records held by vendor |
| Off-site clinic | Employees travel to audiologist or occupational health clinic for testing | Clinical-grade environment; professional oversight on-site | Major productivity loss (travel time + wait time); difficult to coordinate for large workforces |
| In-house audiometric testing | Employer owns or leases audiometric equipment; testing conducted on-site by OHC technician or automated system | Maximum scheduling flexibility; minimal downtime per employee; records owned by employer; can test more frequently if needed | Equipment and setup investment; staff training required; employer manages compliance |
In-house audiometric testing has become the dominant model for large and mid-sized industrial employers. Advances in automated audiometer technology have made it possible to conduct accurate, OSHA-compliant pure-tone tests without a full-time audiologist on staff -- using validated automated audiometers that guide the employee through the test and record results directly into a compliance platform.
Soundtrace's approach brings this capability to any facility:
The result is a hearing conservation program that costs less per test, produces better compliance data, and reduces employee downtime by up to 65% compared to mobile van testing.
A standard pure-tone air conduction test covering six frequencies per ear takes approximately 7--12 minutes for a cooperative adult subject using automated audiometry. Mobile van testing typically runs longer due to queue time and intake procedures -- often 30--45 minutes total per employee. In-house automated systems with scheduled appointments can reliably complete testing in under 9 minutes per employee.
No. OSHA requires audiometers meeting ANSI S3.6 specifications, properly calibrated, used in an environment meeting Appendix D background noise limits. Consumer hearing apps and web-based hearing screeners do not meet these technical requirements and cannot produce OSHA-compliant audiometric records.
OSHA requires audiometric records to be retained for the duration of employment. Upon termination, OSHA's general records access provisions apply -- former employees have the right to access their records within 15 working days of a request. Many occupational health attorneys recommend retaining audiometric records for at least 30 years beyond termination due to the latency period of occupational hearing loss claims.
OSHA requires employers to offer audiometric testing at no cost -- it does not compel employees to submit to it. If an employee refuses, document the refusal in writing. The employer has met its obligation by offering the test. However, refusal does not relieve the employer of its obligation to continue offering testing annually and to maintain hearing protection and training requirements.
Clinically, the test itself is the same pure-tone air conduction protocol. The differences are operational: in-house testing is faster per employee, eliminates scheduling dependency on a third-party vendor, keeps records under the employer's direct control, allows flexible scheduling throughout the year rather than a single annual event, and typically costs less per test at scale. Soundtrace's platform provides both the equipment and the professional oversight that would otherwise require a van vendor relationship.
Soundtrace replaces your mobile van with an in-house testing platform that your team can run, with professional audiology oversight built in. Employees are tested in under 9 minutes; STS is flagged automatically; records are always audit-ready.
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