NAABSA

 Not Always Afloat But Safely Aground

NCSA

 North Coast South America

NCV

 No Commercial Value

NDT

 Non Destructive Testing

NEP/S

 Not Elsewhere Provided/Stated

NIMA

 National Imagery and Mapping Agency

NKK

 Nippon Kaiji Kyokai (Japanese Classification Society)

NLS

 Noxious Liquid Substances

NMEA

 National Marine Electronics Association

NOAA

 The United States National Oceanic and Atmospheric Administration

NOE

 Notice of Exception

 Not Otherwise Enumerated

NOP

 Not Otherwise Provided

NOR

 Notice Of Readiness

NORA

 Notice Of Readiness Accepted

NORT

 Notice Of Readiness Tendered

NOS

 Not Otherwise Specified

NPA

 National Petroleum Association

NR

 No Risk

NRAD

 No Risk After Discharge

NRT

 Net Registered Tonnage

NS

 Nuclear Ship

NSPF

 Not Specially Provided For

N/T

 New Terms

NT

 Net Tonnage

NTM

 Notice to Mariners

NUC

 Not Under Command

NVO

 Non Vessel Operating

NVOC

 Non Vessel Owning Carrier

NVOCC

 Non Vessel Owning Common Carrier

NWE

 North West Europe

NYPE

 New York Produce Exchange form