RAM Licensing & Regulatory

Authorized Medical Physicist (AMP)

The AMP is responsible for the technical foundation of the radiation safety program — calibration of instruments, validation of procedures, and program-level review of dosimetry and surveys. For an Ac-225 program, the AMP is the person who confirms that what the AU prescribes is actually what the patient receives.

Responsibilities

Instrument calibration

Validate the Ac-225 setting on the dose calibrator against a traceable source. Confirm alpha-capable survey instruments are calibrated and within service interval.

Dose measurement & verification

Establish the procedure for measuring delivered activity at the point of administration, including how to handle decay correction between calibration time and administration time.

Program review

Periodic review of dosimetry placement, bioassay results, survey records, and incident reports. Sign-off on procedure changes that affect dose, contamination, or shielding.

Engagement timing

Engage the AMP at the licensing-application stage — not at facility commissioning. Alpha-specific calibration and instrument selection should be designed into the program, not retrofitted after a hot lab is built.

Tip

It's worth validating the Ac-225 dial setting on your specific dose calibrator with the AMP and the manufacturer — generic settings can be off by clinically meaningful amounts, and regulators typically ask for the validation record at first inspection.

References

10 CFR §35.51 — Training for an Authorized Medical Physicist.
AAPM Task Group reports on dose calibrator and survey-instrument calibration.