Table 5.18 — ECs whose label begins with N
| Label | Concept definition | Code |
| NAMED_LAND_TRACT | A <TRACT> of natural scenery, defined by its geographical characteristics and known by its proper name. | 788 |
| NAMED_MAP_LOCATION | A <LOCATION> that normally does not appear as a specific, characterized <OBJECT> on a <MAP> but has a name that is required to be placed on the <MAP>. | 789 |
| NATIONAL_PARK | An extensive <REGION> of a particular nature that has been defined by law and is to be protected as a whole; it meets the prerequisites of a <NATURE_RESERVE> for the largest part and has been influenced by <HUMAN>s at most only to a small extent; a national park. | 790 |
| NATURAL_AIR_OBSTRUCTION | An existing <OBJECT> of fixed <<HEIGHT_AGL>> or natural growth at a fixed <LOCATION> within a proscribed <REGION> (for example: adjacent to an <AERODROME>) with reference to which vertical clearance is or must be provided during flight operations; a natural air obstruction. | 791 |
| NATURAL_GAS_RIG | A <RIG> for the collection of natural gas from a <WELL>; a natural gas rig. | 792 |
| NATURE_RESERVE | A <REGION> that has been legally defined and the nature and landscape of which require special protection, be it in part or as a whole, in order to preserve symbioses or biotypes of specific wildlife <NON_HUMAN_ANIMAL>s or <PLANT>s: for scientific reasons; for reasons of natural or geographic history; or because of their rareness, uniqueness, or outstanding beauty; a nature reserve. | 793 |
| NAUTICAL_CLUB | The <BUILDING>s, <GROUNDS>, and <DOCK>s of an organization that promotes and supports yachting, sailing, and boating; a nautical club, yacht club, or sailing club. | 794 |
| NAVIGABLE_WATERWAY | A <WATERCOURSE> that is usable, sometimes after improvements, as a commercial <MARINE_ROUTE>; a navigable waterway. | 795 |
| NAVIGATION_BUOY | A <BUOY> serving as a <MARINE_AID_TO_NAVIGATION>; a navigation buoy. | 796 |
| NAVIGATION_DEVICE | Any visual or electronic <DEVICE>, usually located within a <VEHICLE>, that provides point-to-point guidance information or <LOCATION> data; a navigation device or navigation aid. | 797 |
| NAVIGATION_LIGHT | A specially constructed <DEVICE> that displays a <LIGHT> as an <AID_TO_NAVIGATION>; a navigation light. | 798 |
| NAVIGATION_LINE | A <LINE> between two <AID_TO_NAVIGATION>s that extends towards the <REGION> of navigational interest; a navigation line. | 799 |
| NAVIGATION_MARK_AFLOAT | A floating <STRUCTURE> providing a reference <LOCATION> for navigation; an afloat navigation mark. | 800 |
| NAVIGATION_MARK_FIXED | A fixed <STRUCTURE> providing a reference <LOCATION> for navigation; a fixed navigation mark. | 801 |
| NAVIGATION_RADAR_RANGE | A <WATERBODY_REGION> within range of a <RADAR_STATION>; inside this <REGION> a <VESSEL> may request navigation radar assistance from <SHORE>, particularly in poor visibility. | 802 |
| NAVIGATION_RESTRICTED_REGION | A <REGION> in which certain aspects of navigation are restricted. | 803 |
| NEAP_TIDE | The <TIDE>s of decreased range occurring near the times of the first and last quarter <<MOON_PHASE>>s. | 804 |
| NEARSHORE_PRECISE | The <TERRAIN_STRIP> that is located between the 10 metre <DEPTH_CURVE> and the <LOW_WATER_LINE> defined by either mean low water springs or mean lower low water as defined by the applicable National Authority; nearshore precise. | 805 |
| NEBULA | An immense body of highly rarefied gas and dust in the interstellar spaces of <GALAXY>s; a nebula. | 806 |
| NEPTUNE | The primary <PLANET> of the <SUN> that is normally eighth in distance from the <SUN>, with an orbital mean <<RADIUS>> of approximately 4 504,4 million kilometres; Neptune. | 807 |
| NETWORK | A <SYSTEM> of inter-connected <OBJECT>s of either the same type or directly related types; a network. | 808 |
| NEWSPAPER_PLANT | A <BUILDING> used in the printing, collating, storage, or distribution of a newspaper; a newspaper plant. | 809 |
| NON_AQUEOUS_CLOUD | An <AEROSOL> of non-aqueous <PARTICLE>s (for example: <SMOKE> and/or <DUST>); a non-aqueous cloud. | 810 |
| NON_COMMUNICATION_TOWER | A <TOWER> that is used for non-communication purposes (for example: observation, support, and/or storage). | 811 |
| NON_EMPTY_SET | A <SET> with at least one member; a non-empty set. | 812 |
| NON_HUMAN_ANIMAL | An <ANIMAL> other than a <HUMAN> [SOED, "animal", A.a]. | 813 |
| NON_SUBMARINE_CONTACT | Any <OBJECT> (for example: a <MARINE_WRECK>) on a <WATERBODY_FLOOR> that could be mistakenly identified as an operable <SUBMERSIBLE_VESSEL> when detected with acoustic or magnetic sensors; a non-submarine contact. | 814 |
| NUCLEAR_REACTOR | <EQUIPMENT>, which may be contained within a <POWER_PLANT> or <VESSEL>, in which a nuclear chain reaction is initiated, sustained, and controlled; a nuclear reactor. | 815 |
| NUCLEAR_WEAPONS_FACILITY | A <FACILITY> used for the construction, assembly, storage, or dismantling of nuclear <WEAPON>s. | 816 |
http://www.iso.ch/iso/en/ittf/PubliclyAvailableStandards/ISO_IEC_18025_Ed1.html