| Label | Concept definition | Figure(s) | Attribute value type | EQ label | Code |
|---|---|---|---|---|---|
| UNCOVERING_HEIGHT_KNOWN | An indication that information is known about the <<HEIGHT>> to which a <MARINE_OBJECT> may be uncovered by the <TIDE>; uncovering height known. | BOOLEAN | 1487 | ||
| UNDERBRIDGE_CLEARANCE | The clearance below a <BRIDGE> measured from the lowest level of the bridged <SURFACE> to the base of the lower of either a cross <STRUCTURAL_BEAM> or lowest deck of the <BRIDGE>; underbridge clearance. | REAL | LENGTH | 1488 | |
| UNDERLYING_MATERIAL- _CHARACTERISTIC |
The characteristics of the composition of the <MATERIAL> underlying the <SURFACE> of an <OBJECT>. | ENUMERATION | 1489 | ||
| UNDERLYING_MATERIAL_TYPE | The type of composition of the <MATERIAL> underlying the <SURFACE> of an <OBJECT>. | ENUMERATION | 1490 | ||
| UPSTREAM_HEIGHT | The height of an <OBJECT> above a <WATERCOURSE> measured on the upstream side. | REAL | LENGTH | 1491 | |
| URBAN_BUILDING_LIGHTING- _INTENSITY |
A number between 0 and 1 inclusive representing the linearly-scaled fractional intensity of the <LIGHTING> on an urban <BUILDING>. Zero means unlit and one means maximum intensity. | REAL | PURE_NUMBER | 1492 | |
| URBAN_STREET_LIGHTING- _INTENSITY |
A number between 0 and 1 inclusive representing the linearly-scaled fractional intensity of the <LIGHTING> on an urban <STREET>. Zero means unlit and one means maximum intensity. | REAL | PURE_NUMBER | 1493 | |
| URBAN_STREET_PATTERN | The predominant geometric configuration of <STREET>s found within a delineated <TERRAIN_SURFACE_REGION>; urban street pattern. | ENUMERATION | 1494 | ||
| URBAN_TERRAIN_ZONE_TYPE | The type of an urban terrain zone based on the characterization of <BUILDING>s and their density. | ENUMERATION | 1495 | ||
| USABLE_LENGTH | The usable <<LENGTH>> of an <OBJECT>. | REAL | LENGTH | 1496 | |
| UTILITY_USE | The type of a <FACILITY> that is used for utility provision purposes; utility use. | ENUMERATION | 1498 |
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