ABSTRACT
Radiography of the chest remains one of the most commonly performed examinations, but still there is a considerable number of repeated examination due to poor quality, this arises from many factors; the exposure factors selection are the crucial one. The selection of these factors mostly depends on the experience of the technologist and sometimes on the theoretical basis which might not gives satisfactory results. This study was done to evaluate the factor that affects the exposure factor selection and hence to develop an empirical system that gives the optimum exposure factors and tests the accuracy and the reliability of the developed system. The study consists of 64 patients examined for PA chest X-ray selected randomly. The collected data includes: chest thickness, body mass index, age, height in addition to KV and MAs. The results showed that the body mass index and the patient weight were linearly correlated with the Kv and MAs respectively