10 C.F.R. § 850.24
(a) General. The responsible employer must ensure that:
(b) Initial monitoring. The responsible employer must perform initial monitoring in areas that may have airborne beryllium, as shown by the baseline inventory and hazard assessment. The responsible employer must apply statistically-based monitoring strategies to obtain a sufficient number of sample results to adequately characterize exposures, before reducing or terminating monitoring.
(g) Notification of monitoring results.
(1) The responsible employer must, within 10 working days after receipt of any monitoring results, notify the affected workers of monitoring results in writing. This notification of monitoring results must be:
(2) If the monitoring results indicate that a worker's exposure is at or above the action level, the responsible employer must include in the notice: