Grant W, Cundiff J, Hanson W, Gagnon W, Shalek R
Med Phys. 1976;3(5):353-4. doi: 10.1118/1.594266.
The Keithley model 602 electrometer-Farmer ionization chamber combination has served as the standard dosimetry system for calibration measurements made by the AAPM Radiological Physics Center at 156 different institutions. The constancy of this system is compared to that for the Baldwin-Farmer Secondary Standard Dosemeter type 2502, and is based on measurements made over a 3-yr period on a Cobalt-60 gamma-ray source. A Strontium-90 check source is also shown to be a reliable standard, and frequent checks with such a source can prevent serious calibration errors.
吉时利602型静电计 - 法默电离室组合一直是美国医学物理学家协会放射物理中心在156个不同机构进行校准测量时所采用的标准剂量测定系统。该系统的稳定性与鲍德温 - 法默2502型二级标准剂量仪的稳定性进行了比较，并且基于在一个钴 - 60伽马射线源上进行的为期3年的测量。锶 - 90校验源也被证明是一个可靠的标准，并且使用这样一个源进行频繁校验可以防止严重的校准误差。
