Testing Laboratory
Conditioning sets the floor on turnaround. Technician hours set the ceiling on throughput.
— %
Test hours demanded against productive bench hours available
Utilisation here is against productive hours, not shift hours, so it is directly comparable between laboratories only if the productive fraction is measured the same way. The turnaround figure assumes the day's work is shared evenly across technicians and that no test is a blocking dependency for another; where a sequence is mandatory - conditioning, then dimensional stability, then wash testing on the same specimen - the true turnaround is the sum of the chain, not the divided total. The queue term only accumulates a single day of backlog; a laboratory persistently over 100% compounds day on day and this model will understate turnaround badly after the first week. Retained mass assumes a constant retention policy across all sample types, which is rarely true: fibre and yarn retentions are small, garment retentions are not.
Laboratory Sample Chain-of-Custody, Load & Turnaround — free, with the formula and a worked example, at Textile School.