Reference : Instrumentation QC

The following tables list the frequency that you have to do QC's for different instruments. These are general guidelines. Your camera may have different requirements.

ps: For a great article describing how to do each calibration, read this.

pps: You need to keep all qc records for 3 years. Actually, if you ever get asked how long you need to keep a record for, it is 3 years for just about everything.

Dose Calibrator QC

Frequency QC Suggested Limit Trigger Limit
Daily Constancy <5% <10%
Quarterly Linearity <5% <10%
Annually Accuracy <5% <10%
On Install/Repair Geometry Manufacturer performs test -

Gamma Camera QC

Frequency QC
Daily Uniformity (Flood)
Weekly Spatial Resolution/Linearity (Bars)
Quarterly High Count Flood (100million counts)
Monthly (SPECT Cameras Only) Center of Rotation
Quarterly (SPECT Cameras Only) SPECT Resolution (phantom)

PET QC

Frequency QC
Daily Blank Scan
Daily Background Counting Rate
Quarterly Normalization
Quarterly Absolute Activity Calibration

Dose Calibrator QC details

Basically, for dose calibrators: <5% variation is suggested, but <10% is a trigger level that legally requires action. The following is paraphrased from NRC 10CFR35.50:

  1. Constancy:

    Check each dose calibrator for constancy with a dedicated check source at the beginning of each day of use. The check must be done on a frequently used setting with a sealed source of not less than 10 microcuries of radium-226 or 50 microcuries of any other photon-emitting radionuclide. If reading varies more than 10% of the expected activity, repair machine.

  2. Accuracy:

    Test each dose calibrator for accuracy upon installation and at least annually thereafter by assaying at least two sealed sources containing different radionuclides whose activity the manufacturer has determined within 5 percent of its stated activity, whose activity is at least 10 microcuries for radium-226 and 50 microcuries for any other photon-emitting radionuclide, and at least one of which has a principal photon energy between 100 keV and 500 keVIf readings varies more than 10% expected, repair machine.

  3. Linearity:

    Test each dose calibrator for linearity upon installation and at least quarterly thereafter over a range from the highest dosage that will be administered to a patient or human research subject to 1.1 megabecquerels (30 microcuries) If the reading is greater than 10% of expected, you need to use correction factors for readings in those ranges. These corrections need to be posted near the instrument.

  4. Geometry:

    Test each dose calibrator for geometry dependence upon installation over the range of volumes and volume configurations for which it will be used. The manufacturer usually does this test, you just have to keep the record. This also needs to be done after the instrument sent in for repair.