The audiometric schedule is where most hearing conservation programs go wrong, because the clock starts on exposure, not on the calendar year.
Baseline. Within 6 months of an employee's first exposure at or above the action level, the employer must establish a valid baseline audiogram against which subsequent audiograms can be compared (29 CFR 1910.95(g)(5)(i)). The action level is an 8-hour time-weighted average of 85 decibels, and it is the trigger for the whole program (29 CFR 1910.95(c)(1)).
The mobile-van exception. Where mobile test vans are used to meet the audiometric obligation, the baseline must be obtained within 1 year of first exposure; where baselines are obtained more than 6 months after first exposure, employees must wear hearing protectors from the end of the sixth month until the baseline is taken (29 CFR 1910.95(g)(5)(ii)).
Quiet before the test. Testing to establish a baseline must be preceded by at least 14 hours without exposure to workplace noise; hearing protectors may be used as a substitute for that quiet period, and employees must be told to avoid high non-occupational noise during the 14 hours (29 CFR 1910.95(g)(5)(iii), (g)(5)(iv)).
Annually after that. At least annually after obtaining the baseline, the employer must obtain a new audiogram for each employee exposed at or above the 85 dBA action level (29 CFR 1910.95(g)(6)). Annual audiograms are compared with the baseline to determine whether a standard threshold shift has occurred (29 CFR 1910.95(g)(7)).
A new hire who starts in March on a 90 dBA line needs a baseline by September. Scheduling everyone's audiograms in December satisfies the annual requirement for existing employees and quietly misses it for that hire.