Reliability

Reliability is the probability that a system performs to a level consistent with the system specification. The term was added to the National Construction Code (NCC) 2022 edition as a consequence of including quantified Performance requirements for automatic warning (H3P2) for occupants.1

Automatic warning for occupants (H3P2)1
In a Class 1 building, occupants must be provided with automatic warning on the detection of smoke with an efficacy greater than 0.95 and a reliability greater than 0.95, so that they may evacuate in the event of a fire to a place of safety appropriate to the—

1. function and use of the building;and 
2. occupant characteristics; and
3. fire load and combustion characteristics; and
4. potential fire intensity; and
5. fire hazard.

• 1a1b

  NCC 2022 Volume Two - Building Code of Australia