FSM - Refresh Cache (Full) - When and Why

We are looking for some sort of documentation containing clear guidelines on:

1. what type of change requires a Refresh Cache (FULL) e.g.
   1. business rules
   2. app_params
   3. screen designs
   4. client scripts
   5. scheduled processes
   6. etc.
2. when is it recommended to execute the Refresh Cache (FULL)
   1. anytime
   2. off hours
   3. scheduled outage

Is there a technical paper to help explan this.  Up until now we have been given conflicting guidance on this and need to get a better level of understanding of the When and Why.