Category 1 Operations of Subpart D of Part 107 is described as?

To conduct Category 1 operations - (a) A remote pilot in command must use a small unmanned aircraft that - (1) Weighs 0.55 pounds or less on takeoff and throughout the duration of each operation under Category 1, including everything that is on board or otherwise attached to the aircraft; and (2) Does not contain any exposed rotating parts that would lacerate human skin upon impact with a human being. (b) No remote pilot in command may operate a small unmanned aircraft in sustained flight over open-air assemblies of human beings unless the operation meets the requirements of either 89.110 or 89.115(a) of this chapter.