NCHRP: National Cooperative Highway Research Program
NCSL: National Conference of State Legislatures
NEMA: National Electrical Manufacturers Association
NEPA: National Environmental Policy Act of 1969
NFIRS: National Fire Incident Reporting System
NHI: National Highway Institute
NHS: National Highway System
NHTSA: National Highway Traffic Safety Administration
NIA: National ITS Architecture
NIPC: National Infrastructure Protection Center
NIST: National Institute of Standards and Technology
NMEA: National Marine Electronics Association
NOAA: National Oceanic and Atmospheric Administration
NOx: Nitric Oxide
NTCIP: National Transportation Communications for ITS Protocol
NTP: Network Time Protocol
NWS: National Weather Service