II Morrow Inc. NMC 2001 Operating Manual page 323

RAIM Operations
Note that the three different equipment operation states: En route,
Approach-Transition, and Approach-Active are somewhat but not
directly related to the three RAIM alarm limits of En route, Terminal,
and Approach. The equipment states are defined by the CDI sensitivity
and operational requirements. When you depart an airport, the
equipment is operating En route, but it is providing Terminal RAIM
integrity. When you reach a point 30 nm from your destination airport,
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