Farai I P, Kadni T
Department of Physics, University of Ibadan, Nigeria.
Afr J Med Med Sci. 2000 Sep-Dec;29(3-4):219-21.
The absorbed dose water in a Co-60 teletherapy beam has been measured with four different standard ionisation chambers applying two codes of practice and also, with a Fricke dosimeter. Measured values agree generally within 2.3%. There is a remarkable agreement of less than 0.3% variation, between ionisation chambers NE 2561 and NE 2481 when the IAEA protocol is applied. The HPA protocol is applicable to only NE 2561 and a variation of about 1.4% was observed between measurements made with this ionisation chamber applying the two protocols. The IAEA protocol shows very accurate results. With a deviation of about 2.2%, the Frickle dosimeter appears to be the least accurate for therapy dose measurement despite its simplicity of application.
使用四个不同的标准电离室，应用两种操作规范，还使用弗里克剂量计，对钴 - 60远距离治疗束中的吸收剂量水进行了测量。测量值总体上在2.3%以内相符。当应用国际原子能机构（IAEA）的协议时，电离室NE 2561和NE 2481之间的变化小于0.3%，存在显著的一致性。健康保护局（HPA）的协议仅适用于NE 2561，使用该电离室应用这两种协议进行测量时，观察到约1.4%的变化。IAEA协议显示出非常准确的结果。尽管弗里克剂量计应用简单，但对于治疗剂量测量来说，其偏差约为2.2%，似乎是最不准确的。
