UAS (Unmanned Aerial Systems) are considered a hot topic operating in dark, fog, and difficult decreased visibility situations. Moreover, this low cost off-the self equipment combines computer vision that is sophisticated for aerial view in confined areas when manned helicopter cannot operate. A diverse array of these appliances includes aeronautical and engineering aspects while some others are capable to access structures using GPS systems. Bridging the gap with this lack of standardization to a certain degree dedicated to drones is like standing in front of the door of future since airworthiness Standards are not available, except for Federal Aviation Administration Modernization and Reform Act of 2012 and Code of Federal Regulations. The objective of this paper is to prioritize and quantify risk framework regarding safety constraints via a Fuzzy Inference System (FIS). This contribution is a brief and easily understood overview of drones and fundamental constraints that are being proposed. The upper goal of the paper is the defuzzification of safety requirements on the base of computer software as MATLAB, since we live in the century of information, with aim to succeed in overall hierarchy of mitigation efforts.