How Soon Do Mobile Hearing Test Results Come Back and Get Reviewed?

How long does it take to get mobile hearing test results back?

For most employees tested in a mobile hearing conservation program, the technician's comparison against the baseline audiogram happens the same day, often within minutes of the test itself, because the comparison step is largely automated in modern audiometers. What takes longer is everything downstream of that first-pass comparison: confirming a flagged result isn't a booth noise artifact or a fit issue, routing any suspected standard threshold shift (STS) to the supervising professional, and generating the paperwork the employer needs for the file. An employer asking "when do we get results" is really asking about two different clocks: the same-day pass/fail comparison, and the days-to-weeks professional review and notification cycle that follows when something shows up on that comparison.

Who actually reviews the audiogram, and how fast?

Under 29 CFR 1910.95(g), a technician can perform the initial comparison between an employee's annual audiogram and their baseline to determine whether a standard threshold shift occurred, but that technician works under the responsibility of an audiologist, otolaryngologist, or physician. For the large majority of tests that show no shift, this review is effectively instantaneous and the result simply gets filed. For a test that does show a shift, the clock that matters is the one OSHA actually writes down: a professional review of the questionable case, and if confirmed, a written notification to the employee within 21 days of determining the STS occurred. That 21-day window is the single most concrete, enforceable results-timeline number in the standard, and it's the one employers most often get wrong by confusing "test day" with "determination day."

What happens if the first annual test shows a shift?

1910.95(g) gives employers an option that directly affects how fast a final result comes back: if the annual audiogram shows an STS, the employer may retest within 30 days and treat that retest as the annual audiogram of record instead of the original. This exists because a single test can be thrown off by a cold, an ear infection, or recent non-occupational noise exposure, and a same-cause retest often clears the flag. Practically, this means an employee who shows a shift on test day may not get a final answer until the retest happens, which can push the real "result" out closer to a month from the original test, well past what most people picture when they think of same-day mobile testing results.

Milestone	Typical timing	Governing requirement
Technician comparison vs. baseline	Same day as test	1910.95(g) technician comparison, under professional responsibility
Optional retest after a flagged STS	Within 30 days of the original test	1910.95(g) retest-as-annual-audiogram option
Written employee notification of a confirmed STS	Within 21 days of the determination	1910.95(g)(8)
OSHA 300 Log recording of a recordable STS case	Within 7 calendar days of determining the case is recordable	29 CFR 1904.10

When does a shift have to show up on the OSHA 300 Log?

A confirmed STS doesn't automatically become an OSHA-recordable case. Under 29 CFR 1904.10, a case is recordable only when the shift is work-related, confirmed as an STS (a 10 dB or greater average shift at 2000, 3000, and 4000 Hz in one or both ears relative to baseline), and the employee's total hearing level in the affected ear is 25 dB or more above audiometric zero when averaged across those same frequencies. Once all three conditions are met, the employer has 7 calendar days to enter the case on the OSHA 300 Log. That 7-day clock starts at the recordability determination, not at the original test date, which is why a plant's safety manager needs the professional review finished promptly rather than letting flagged results sit in a queue.

Why do employers get the timeline wrong?

The most common mistake is treating the mobile van's departure as the end of the transaction. A van can leave the site with same-day pass/fail data for every employee tested, but a handful of flagged cases are still mid-review, and if the employer doesn't track which employees are in that pending group, the 21-day notification and 7-day recording clocks can quietly run out unnoticed. The second common mistake is assuming a flagged result is final the moment it's flagged, which leads to premature notifications or Form 300 entries for cases that clear on a legitimate retest. Both mistakes come from the same root cause: not separating "tested" from "reviewed" from "determined" as three distinct events with three different dates.

How Foster handles mobile test result turnaround

Foster's mobile hearing testing sends same-day pass/fail comparisons for the full roster, but any employee whose annual audiogram flags against their baseline gets routed separately to the supervising professional rather than held in a general batch, so the 21-day notification clock starts running against an accurate determination date instead of the test date. We track retest eligibility on flagged cases so a plant knows within the 30-day window whether a shift is confirmed or clears, and we hand the employer the dates needed for 1904.10 recordkeeping rather than leaving that calculation to the safety manager after the fact. Foster's hearing testing services and on-site testing scheduling are built around keeping these three dates (test, determination, notification) separate and documented. For the deadline math on getting a delayed test rescheduled without losing ground on the annual cycle, see Foster's post on mobile hearing test rescheduling and the OSHA deadline.

FAQ

Do all mobile hearing test results come back the same day?

The initial technician comparison against baseline is same-day for essentially every employee. Only flagged cases, where a shift shows up, require additional professional review and possibly a retest before a final result is ready.

How long does an employer have to notify an employee of a standard threshold shift?

21 days from the date the STS is determined, under 1910.95(g)(8), not 21 days from the original test date.

Can a flagged result be retested before it counts as the annual audiogram?

Yes. 1910.95(g) allows a retest within 30 days of the original test, and the employer may treat that retest as the annual audiogram of record instead of the flagged original.

How fast does a confirmed STS have to be recorded on the OSHA 300 Log?

Within 7 calendar days of determining the case meets all three 1904.10 recordability criteria: work-relatedness, a confirmed STS, and a 25 dB or greater total hearing level in the affected ear.

Why would a shift on test day not end up on the OSHA 300 Log?

Because recordability requires all three 1904.10 criteria. A confirmed STS that doesn't also meet the 25 dB total hearing level threshold, or that isn't work-related, doesn't get recorded even though it was a real shift from baseline.

Sources

• OSHA 29 CFR 1910.95 standard text
• OSHA 29 CFR 1904.10 standard text
• J. J. Keller: 1904.10 recording criteria for occupational hearing loss