Knowledge Hub · Saxsons Dose Dispenser
The dose-withdrawal step accumulates operator extremity dose faster than any other point in the dispensing workflow. The tiltable mechanism + 3-part vial-shield architecture keeps the vial in the shielded base across the multi-dispense campaign; only the top cap moves per dispense.
Tiltable mechanism vs lift-out
The dose-withdrawal step — needle into the source vial — is where operator extremity dose accumulates fastest in the radiopharmacy. A lift-out workflow brings the unshielded vial out of the shielded chamber, exposes the operator hand to the source, then re-shields. A tiltable dispenser brings the needle hole DOWN to the operator-held syringe; the vial stays in the shielded base across the multi-dispense campaign. The per-dispense extremity dose drops measurably vs lift-out-and-withdraw.
Source: AAPM Report 88; ICRP Publication 103 (500 mSv extremity-dose limit).
3-part vial-shield architecture
The 3-part Lead Pot or Tungsten 3-part vial-shield = Top Cap (closes needle hole) + Middle Cap (with needle access hole) + Base (holds vial). Per dispense: lift top cap, withdraw dose, replace top cap. The Middle Cap and Base do not move. The vial NEVER comes out of the shielded base across the multi-dispense campaign. Operator hand approaches an unshielded source ONLY at the syringe-needle interface for the few seconds of the withdraw.
Pb vs Tungsten tier choice
30 mm Pb 3-part Lead Pot delivers ~ 7 HVL at 511 keV. 20 mm Tungsten 3-part vial shield delivers similar attenuation in a smaller, denser chassis (W density 19.3 g/cm³ vs Pb 11.3 g/cm³). Radiopharmacies preferring lead pick the 30 mm Pb tier (30 cc vial geometry). Radiopharmacies wanting the smaller / lighter chassis pick the 20 mm Tungsten tier (15 cc vial geometry). Same dispense workflow, two material-tier options.
Source: NIST XCOM cross-section database; NCRP Report 49 HVL framework.
Mechanism ergonomic variants
Three mechanism variants deliver the same shielded outcome. Tiltable (RPDD1-A series) is the workhorse — the operator tilts the lead pot to bring the needle down. Swivel-jaw (RPDD1-C series) is the ergonomic alternative — rotational swivel brings the vial neck to the operator-syringe at a fixed working height. With-rod (RPDDS-B / RPDD1-B series) is the leverage-preferred variant. The radiopharmacy picks per operator preference and physical layout.
Source: IAEA Operational Guidance on Hospital Radiopharmacy (operator-ergonomics chapter).
Pairs with the Saxsons L-Bench + Vial Shield range
The dose dispenser sits on the Saxsons L-Bench PET worktop (NM-036) next to the dose calibrator. It uses the Saxsons Lead Vial Shield (NM-034 — 30 mm Pb 3-part PET) or Saxsons Tungsten Vial Shield (NM-035 — 20 mm 3-part PET). The dispensed dose goes into the Saxsons PET tungsten syringe shield (NM-032) for the dispense-bench-side handling step. The full Saxsons hot-lab fit-out covers dispense → calibrate → shield → transport → inject as one end-to-end workflow chain.
Source: Saxsons hot-lab fit-out reference catalogue; AAPM 88 radiopharmacy workflow design.
Dispenser-ergonomics and 3-part vial-shield physics framework.
AAPM framework for radiopharmacy QC including dispensing-workflow ergonomics.
Current ICRP framework defining the 500 mSv/year extremity-dose limit.
IAEA framework — operator protection at the dispense step.
Authoritative photon attenuation reference for Pb vs W at 511 keV.
Indian regulatory framework for PET dispensing equipment.