title: Dosimetric quality control measurements of 60Co teletherapy units in Nigeria.
abstract: Measurements of output dose rates of four Co teletherapy machines located in three hospitals in Nigeria have been made using the facilities of the Secondary Standard Dosimetry Laboratory at Federal Radiation Protection Service in Ibadan, Nigeria, and by applying an International Atomic Energy Agency dosimetric protocol. The results show that the percentage deviation between our measured dose rates and dose rates employed by the users ranged generally between 0.15% and 10.6% relative to our measured dose rates. For one of the machines, the deviation was consistently within the acceptable limit of +/-5%, while for another it was within this range 75% of the time. For the other two machines the deviation was outside this limit for all of the few measurements that were possible.
authors.affiliation: Department of Physics, University of Ibadan, Ibadan, Nigeria, Africa.
authors.forename: I P
authors.initials: IP
authors.lastname: Farai
authors.forename: R I
authors.initials: RI
authors.lastname: Obed
mesh_terms: D003037:Cobalt Radioisotopes / Q000032:analysis* / Q000592:standards*; D004868:Equipment Failure; D019544:Equipment Failure Analysis / Q000379:methods / Q000592:standards*; D006801:Humans; D009549:Nigeria; D011785:Quality Assurance, Health Care / Q000379:methods / Q000592:standards*; D011786:Quality Control; D011835:Radiation Protection / Q000379:methods / Q000592:standards; D011874:Radiometry / Q000379:methods* / Q000592:standards*; D011878:Radiotherapy / Q000295:instrumentation* / Q000592:standards*; D011879:Radiotherapy Dosage / Q000592:standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003037:Cobalt Radioisotopes