This scientific research aims show the balance CO2 in the block “G” of UNICAP, analyzing specimens extracted from the main structural elements (beams, pillars and slabs); Describe the history of the structure; constructive method; design parameters, comparing the regulatory requirements of the time with the current ones and geographic location. The building in question is “Block G” of the Catholic University of Pernambuco (UNICAP), Built in 1980, located in the city of Recife, at a distance of 500m from the Capibaribe River and 2.02 km from the Atlantic Ocean. Emphasizing the identification of the presence of aggressive agents, mainly carbon dioxide with phenolphthalein spray, but also chloride ions, with silver nitrate (AgNO3) spray. Specimens extracted from the pillars, slabs and beams of the longest facades of the building. Totaling 90 specimens analyzed, distributed among nine floors. A microscopic analysis of the concrete was also carried out, with the analysis in the scanning electron microscope (MEV), with seven specimens, in order to understand its structure, correlating defects and properties and identifying the properties of the materials used. To verify the concrete compressive strength of the structure and compare it with the design parameters, a compressive strength test was performed on seven specimens in a specialized laboratory. Through the results obtained, we can verify which areas of the building are most affected and analyze the results of emission CO2 in environment as relate the CO2 captured by the structure. The identification of these agents demonstrates how the structure is suffering with a high probability of corrosion and degradation? what kinds of structural maintenance and recovery and which agents in each position on bulid, in view of their geographical position in relation to the sea and effect of the region's winds, in addition to analyzing the design parameters used at the time compared to the current ones and identifying their evolution and efficiency.