Augmented reality (AR) is receiving ongoing attention. With the ability to inject virtual objects into a real environment, an immense variety of use cases can be found. Ranging from entertainment and driving assistance to industrial applications, such as human-robot interaction. Through the release of better and more reliable head-mounted displays, AR also shows potential to be used to increase situational awareness, and thus the user’s safety. This work contributes by investigating the characteristics of AR visualizations that have the purpose of enhancing the situational safety of the user. Therefore, we constructed our taxonomy with a set of 55 articles, which we classified into five dimensions: (1) Purpose of the visualization, (2) Data, (3) Visualization Method, (4) Application Domain, and (5) Interaction with the visualization. On the basis of this taxonomy, we extracted specifications for possible applications. To demonstrate some of these, we implemented a prototype.