This chart describes how systems often avoid failure. The resilience model is based on the  primary hazard model ..., with extra protection layers:

PL1 - trigger prevention

PL2 - rebounding design

PL3 - recovery design

PL4 - escalation prevention

PL5 - rescue design

PL6 - proactive testing

PL7 - investigation design

Updated on 12 Dec 2016.