From the FAA aviation safety inspector’s (ASI) Handbook, (FAA Order 8900.1, Volume.4, Chapter 1, Section 2, Paragraph 4-24).
Examples of special areas of operation include the following:
Areas of Magnetic Unreliability (AMU) and Polar operations
North Atlantic Minimum Navigation Performance Specification (NAT/MNPS) airspace
Central East Pacific (CEPAC) airspace
North Pacific (NOPAC) airspace
Pacific Organized Track System (PACOTS)
West Atlantic Route System (WATRS) and the Caribbean Sea
Gulf of Mexico control areas (Gulf routes)
Reduced Vertical Separation Minimum (RVSM)
Required Navigation Performance (RNP)-10,4 ect.
Examples of special Navigation Equipment include the following:
Area Navigation (RNAV)
Inertial navigation or reference systems INS, IRS or GPS