[en] In chest CT Image acquisition protocols should be based on research to maintain or improve the image quality and reduce risks due to the use of ionizing radiation For this reason, evaluation of the patient’s mass and volume needs to be observed, the analysis of the optical density, the dose measurement and contrast are some factors to be considered to optimize the parameters for image acquisition with diagnostic quality. The Study to determine the low dose study using radio chromic film Low dose chest CT- dose chamber assessment by using CTDI head and body phantom with ionization chamber and radio chromic film CTDI phantom will undergo CT acquisition with low dose protocols containing changes in: Kvp, mAs, Gantry rotation In the study it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. Absorbed dose records by the radio chromic film strips for each position of measurement in the phantom were similar to the values obtained by the pencil ionization chamber. Film strips may be used as a reliable tool in the analysis of absorbed dose, in the search for optimizing the acquisition protocols for HRCT scan