System FMEA is the highest-level analysis of an entire system, made up of various subsystems. The focus is on system-related deficiencies, including system safety, system integration, interfaces or interactions between subsystems or with other systems, interactions with the surrounding environment, human interaction, service, and other issues that could cause the overall system not to work as intended. In System FMEA, the focus is on functions and relationships that are unique to the system as a whole (i.e., do not exist at lower levels). The System level FMEA includes failure modes associated with interfaces and interactions in addition to considering single-point failures (where a single component failure can result in complete failure of the entire system). Some practitioners separate out human interaction and service into their own respective FMEAs.
As you can see from this description of System FMEA, the scope is not set in stone. It is up to the FMEA team (and supporting management) to determine the exact scope of individual FMEAs. In answer to your question # 1, there are two approaches that practitioners use.
One approach is to do two different FMEAs: a System FMEA which includes just the device system itself and not the interactions/interfaces with users and patients, and a separate Human Factors (or Application) FMEA, which covers only the interactions/interfaces between the system and the users and patients.
The second approach is to do a more comprehensive System FMEA, which includes within its scope the interactions/interfaces with users and patients in addition to device system. International standards or company policy may dictate which approach you are required to use, so it is important to familiarize yourself with appropriate standards and policy.
Regardless of which approach you use, be sure to make the scope visible through the use of a properly done FMEA Block Diagram. This will show clearly the scope of your FMEA, including interfaces with humans.
