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Primary Standards for Brachytherapy Sources



Michael G. Mitch, Christopher G. Soares


The AAPM dosimetry protocol for LDR brachytherapy seeds that emit x-rays of energies ≤ 50 keV is described in the TG-43U1 report (Rivard et al. 2004). In this protocol, it is specified that the strength of such sources be expressed in terms of air-kerma strength, traceable to the National Institute of Standards and Technology (NIST). NIST maintains and disseminates the primary air-kerma strength standard for all 125I, 103Pd, and 131Cs seed models.
2009 AAPM Summer School
Publisher Info
AAPM, College Park, MD


absorbed dose, air-kerma, brachytherapy, dosimetry, well chamber


Mitch, M. and Soares, C. (2009), Primary Standards for Brachytherapy Sources, 2009 AAPM Summer School, AAPM, College Park, MD, [online], (Accessed April 20, 2024)
Created June 1, 2009, Updated February 19, 2017