accuracy in these early assessments is much less than for the measurements which will be used for the
final dose assessment.
Provisions for assuring that a worker has received the appropriate in vivo measurements or has
provided the scheduled excreta sample should not be overlooked in designing a program. A reasonable
grace period is appropriate to deal with workers who forget to submit excreta samples or who are unable
to meet the schedule. For some routine sampling frequencies, a grace period of 30 or 60 days may be
appropriate. However, administrative actions (e.g., work restriction) may be appropriate for a worker
who is substantially overdue for measurement.
Ideally, results of new-hire or baseline measurements should be available before a worker
commences the work requiring the bioassay. This prevents loss of baseline information if a sample is lost
during analysis. However, loss during analysis tends to be a rare occurrence, and it is an acceptable
practice to begin work once the sample has been collected but prior to receipt of results.
Where air sample results form the basis for identifying intakes and making preliminary dose
assessments, some kind of initial results (e.g., gross alpha or gross beta concentration) should be available
within a few hours of obtaining the sample. This is particularly important for samples used to monitor for
unknown or changing work conditions. Routine air samples for well-established processes and facilities
may have longer turnaround times (e.g., as much as a few days), provided they are not the sole method of
detecting off-normal workplace conditions.