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Comparison of the NIST and BIPM Standards for Air Kerma in Medium-Energy X-Rays



D T. Burns, C M. O'Brien


A comparison has been made of the air-kerma standards for medium-energy x-rays of the National Institute of Standards and Technology (NIST) and the Bureau International des Poids et Mesures (BIPM). The comparison involved a series of measurements at the BIPM and the NIST using the air-kerma standards and three NIST reference-class transfer ionization chamber standards. Reference beam qualities in the range from 100 kV to 250 kV were used. The results show the standards to be in reasonable agreement within the combined standard uncertainty of the comparison of 0.37 %, although a significant trend with radiation quality is observed and the possible sources discussed.
Journal of Research (NIST JRES) -
111 No. 5


air kerma, free-air ionization chamber, medium-energy x-rays, primary standard, reference radiation qualities, x-ray calibration


Burns, D. and O'Brien, C. (2006), Comparison of the NIST and BIPM Standards for Air Kerma in Medium-Energy X-Rays, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 18, 2024)


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Created September 30, 2006, Updated October 12, 2021