01
The unit of throughput is elements-per-hour, not badges-per-hour
A badge typically carries 2 – 4 TLD elements (whole-body, extremity, or a mix). The reader's throughput number tells you elements/hour, not badges/hour — dividing by the element count per badge is the actual per-worker read rate. A 300 elements/hour reader handling four-element extremity badges reads 75 workers/hour of continuous carousel loading, which is different arithmetic to what the datasheet's raw throughput suggests.
Source: IEC 61066:2006 §7 — automatic-reader throughput characterisation methodology.
02
Real throughput = raw × duty cycle × validity fraction
The 300 elements/hour figure is the reader in continuous read. Real weekly output = raw × duty cycle (typically 60 – 75 % after carousel loads, anneal cycles, calibration reads and operator breaks) × validity fraction (1 – reject rate). A conservatively-planned service assumes ~200 useful elements/hour from a 300-element/hour reader — which sets the workers × frequency × 4-element accountable capacity.
Source: IAEA Safety Reports Series No. 20 (2004) §6 — service dimensioning + operational duty-cycle assumptions.
03
The audit trail scales with worker count, not just reads
NABL ISO/IEC 17025 requires per-element traceability — every read tied to a serial-numbered TLD element, a calibration record valid at the read moment, a background-batch record and a reviewer signature. Manual services keep this in spreadsheets; that stops scaling around 500 workers. RE-2000's per-element database is what makes the ISO 17025 audit feasible at 5,000 workers. Sizing the reader's throughput is only half the sizing question — the database chain has to survive the same audit.
Source: ISO/IEC 17025:2017 §7 — technical requirements: traceability + records; auditor expectations at high element counts.
04
Cost-per-report shifts around the 500 – 800 workers × frequency mark
Below approximately 500 – 800 workers × monitoring cycles per year (rough — depends on badge-format mix), a manual reader's operator-time cost per report is cheaper than the automatic reader's amortisation + service. Above it, the automatic system pays back on operator time in the first year. The trigger is service scale, not "we should upgrade because we can" — a well-run manual service at 200 workers is more cost-efficient than an under-utilised automatic reader.
Source: IAEA SRS-20 §6.4 — service economic-model guidance; adjusted for Indian labour + amortisation assumptions.
05
Extremity + whole-body from the same reader — configuration matters
The RT extremity configuration reads ring badges (Hp(0.07)) using the same reader instrument as the S/A whole-body cards (Hp(10)). Same anneal cycle, same PMT, same calibration chain — one audit trail, one accreditation scope. Splitting extremity to a separate reader is possible but doubles the calibration + traceability documentation the service has to maintain. Most Indian personal-dosimetry services run whole-body + extremity through one instrument for the ISO 17025 simplicity.
Source: ISO 12794:2000 — extremity + eye-lens dosimeter type-test; IEC 61066:2006 §5 for the reader-side configuration flexibility.
