Assertion: diver's level | /r/HasProperty | derived
Facets:
value: usually
type: DEGREE
value: from understanding the systems
type: OTHER
Source sentences:
text: Rebreathers are more complex to use than open circuit scuba, and have more potential points of failure, so acceptably safe use requires a greater level of skill, attention and situational awareness, which is usually derived from understanding the systems, diligent maintenance and overlearning the practical skills of operation and fault recovery.