The airspace is constantly adapting to efficiently absorb the growing traffic demand in the coming years and may therefore present bottlenecks for safety maintenance, especially in the Terminal Control Area (TMA), where the concentration of aircraft causes them to fly closer to each other. This paper presents a matrix of safety parameters to assess the perception of the safety level after modifications to the airspace, using the TMA from the state of São Paulo/Brazil, as an example for validation, following the implementation of the new airspace circulation in 2021. Through theoretical review, it was possible to delimit the study area and link related research to the presented matrix. The results indicated points of divergence among the surveyed stakeholders, such as speed adjustments which resulted in significant improvements for controllers, while for pilots, improvements were seen in traffic flow and waiting times. Overall, there was a positive perception regarding the decrease in workload in complex airspace, which translates into increased operational safety. Finally, areas for improvement were identified for future terminal designs, particularly regarding the need to reduce potential conflicts.