Comparison of pencil-type ionization chamber calibration results and methods between dosimetry laboratories

- A CT pencil-type chamber was calibrated at eight dosimetry laboratories.
- Three different calibration methods were assessed and compared.
- The “partial irradiation method” is the preferred calibration method.
- Most laboratories achieved high level of agreement (>99%) with the standards.
- Detailed analysis of the assigned uncertainties have been performed.