The investigators and regulators take a dim view of any uncontained failure having demonstrated sufficient energy to penetrate the engine casing itself (I'm not going anywhere in a discussion about parts out the inlet or tailpipe)
However the airplane manufacturer also has to design to accomodate (by minimizing the effects of) any uncontained engine failure and at this point there is a distinction made between high energy particles, low energy particles numbers and trajectories.
The good news (if any) from the standpoint of uncontained engine failures, is that disabling an aircraft to the point of affecting safe flight and landing is quite rare now-a-days. Of course on-the-ground events may have different outcomes.