Inter-comparison of absorbed dose to water in a Co-60 therapy beam using IAEA and HPA protocols.
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.
Farai
I P
IP
Department of Physics, University of Ibadan, Nigeria.
Kadni
T
T
D000042:Absorption; D055592:Biophysical Phenomena; D001703:Biophysics; D002985:Clinical Protocols / Q000592:standards; D003037:Cobalt Radioisotopes / Q000008:administration & dosage*; D003627:Data Interpretation, Statistical; D006801:Humans; D007390:International Agencies; D011867:Radioisotope Teletherapy / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D011879:Radiotherapy Dosage; D012958:Societies, Scientific; D014867:Water / Q000008:administration & dosage*
D003037:Cobalt Radioisotopes; D014867:Water