This contribution proposes a taxonomy of restrictive properties of safety zones in outer space. Based on similar phenomena mainly in the regulation of airspace and the high sea, and with consideration of existing discourse with respect to safety zones in outer space, six main aspects of safety zones that determine its constraining effect on other space actors are identified. Consequently, this paper proposes a dynamic minimality principle when considering how to scope and size a safety zone along the axes of restrictions outlined in the taxonomy.