Article 100 NEC Definitions (Letter K y L)

This article aims to clarify and explain terms that are commonly encountered in electrical engineering projects, focusing on areas such as wiring, system components, locations of installation, and safety protocols.

From kitchen and laundry areas to lighting systems and hazard classifications, mastering this terminology will empower professionals to navigate the complexities of electrical work with confidence and competence.

Kitchen
An area with a sink and permanent provisions for food preparation and cooking. (CMP—2)

Labeled
Equipment or materials to which a label, symbol, or other identifying mark has been attached, indicating compliance with appropriate standards or performance in a specified manner. The labeling is provided by an organization acceptable to the authority having jurisdiction and is periodically inspected. (CMP—1)
Informational Note: If a listed product is too large, small, or textured for a complete label, the label may appear on the smallest unit container.

Laundry Area
An area containing or designed to contain a laundry tray, clothes washer, or clothes dryer. (CMP—2)

Leakage-Current Detector-Interrupter (LCDI)
A device in a power supply cord or cord set that senses leakage current and interrupts the circuit at a predetermined level of leakage current. (440) (CMP—11)

LED Sign Illumination System
A complete lighting system consisting of LED light sources, power supplies, wire, and connectors used in signs and outline lighting. (600) (CMP—18)

Legally Required Standby Systems
Systems that are required by municipal, state, federal, or other codes or governmental agencies to automatically supply power to selected loads in the event of failure of the normal source. These systems are not emergency systems. (CMP—13)

Life Safety Branch
A system of feeders and branch circuits that supplies power for lighting, receptacles, and equipment essential for life safety. It automatically connects to alternate power sources during a power interruption. (517) (CMP—15)

Lighting Assembly, Cord-and-Plug-Connected
A lighting assembly consisting of a luminaire intended for installation in the wall of a spa, hot tub, or storable pool, along with a cord-and-plug-connected transformer or power supply. (680) (CMP—17)

Lighting Assembly, Through-Wall
A lighting assembly intended for installation above grade, on or through the wall of a pool, with two interconnected components separated by the pool wall. (680) (CMP—17)

Lighting Outlet
An outlet intended for the direct connection of a lampholder or luminaire. (CMP—18)

Lighting Track
A manufactured assembly designed to support and energize luminaires that can be repositioned on the track. The length can be altered by adding or subtracting track sections. (CMP—18)

Limited Care Facility
A building or portion used on a 24-hour basis for housing four or more persons who cannot preserve their own safety due to age, physical limitations, or intellectual disabilities. (CMP—15)

Limited Finishing Workstation
A power-ventilated apparatus that confines vapors, mists, dusts, or deposits generated by a limited spray application process. It is not a spray booth or spray room. (CMP—14)
Informational Note: Refer to NFPA 33, Standard for Spray Application Using Flammable or Combustible Materials, Section 14.3 for more on limited finishing workstations.

Line Isolation Monitor
A test instrument that continually checks the impedance from each line of an isolated circuit to ground, with a built-in test circuit. (517) (CMP—15)

Liquid Immersion «o»
A type of protection where electrical equipment is immersed in a protective liquid to prevent ignition of an explosive atmosphere above or outside the liquid. (CMP—14)
Informational Note: See ANSI/UL 60079-6 for more details.

Listed
Equipment, materials, or services included in a list published by an organization that evaluates products or services and maintains periodic inspection. Listed products meet designated standards or have been tested for a specified purpose. (CMP—1)
Informational Note: The means of identifying listed equipment may vary between organizations.

Live Parts
Energized conductive components. (CMP—1)

Load Management
The process in an energy management system that limits the total electrical load to a set value by adjusting individual loads. (CMP—12)
Informational Note: This is sometimes called demand-side management (DSM).

Location, Anesthetizing
A space where flammable or nonflammable inhalation anesthetic agents are administered during examination or treatment. (CMP—15)

Location, Anesthetizing, Flammable
A space where flammable inhalation anesthetic agents are used in the normal course of examination or treatment. (CMP—15)

Location, Damp
Locations protected from weather, subject to moderate moisture but not saturation. (CMP—1)
Informational Note: Examples include partially protected locations like under canopies or marquees, or interior locations such as basements.

Location, Dry
A location that is not subject to dampness or wetness, though it may occasionally experience moisture, such as during construction. (CMP—1)

Location, Remote
A location where a production is filmed or recorded, not including motion picture or television studios. (CMP—15)

Location, Wet
Locations exposed to weather, subject to saturation with water or other liquids, underground, or in direct contact with the earth in concrete slabs or masonry. (CMP—1)
Informational Note: An example includes a vehicle washing area.

Location, Wet Procedure
A space in a patient care area where procedures are performed under wet conditions, involving standing fluids or drenching the work area. (CMP—15)
Informational Note: Routine housekeeping procedures do not classify as a wet procedure location.

Locations, Hazardous (Classified)
Locations where fire or explosion hazards exist due to flammable gases, vapors, combustible dusts, or ignitable fibers/flyings. (CMP—14)

Locations, Unclassified
Locations not classified under any specific hazardous zone, such as Class I, II, III, or Zone 0, 1, or 2. (CMP—14)

Long-Time Rating
A rating based on an operating interval of 5 minutes or longer. (660) (CMP—12)

Loudspeaker (Speaker)
Equipment that converts an AC electric signal into an acoustic signal. (640) (CMP—12)

Low-Voltage Contact Limit
A voltage not exceeding specific limits for various AC and DC voltage types. (680) (CMP—17)

Low-Voltage Suspended Ceiling Power Distribution System
A system serving as a support for a finished ceiling surface and distributing power to equipment via a Class 2 power supply. (393) (CMP—18)

Luminaire
A complete lighting unit consisting of a light source, parts for positioning the light source, and components for connecting to the power supply. A lampholder itself is not a luminaire. (CMP—18)

Luminaire, Dry-Niche
A luminaire intended for installation in a pool, spa, or fountain floor or wall, sealed to prevent water entry. (680) (CMP—17)

Luminaire, No-Niche
A luminaire installed above or below water without a protective niche. (680) (CMP—17)

Luminaire, Wet-Niche
A luminaire installed in a forming shell mounted in a pool or fountain structure, completely surrounded by water. (680) (CMP—17)

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Summary Table

Term	Definition
Kitchen	Area with sink and provisions for food preparation and cooking. (CMP—2)
Labeled	Equipment or materials with a label indicating compliance with standards. (CMP—1)
Laundry Area	Area with a laundry tray, washer, or dryer. (CMP—2)
LCDI	Device in power cord sensing leakage current and interrupting the circuit. (440) (CMP—11)
LED Sign Illumination System	Complete system for LED signs, including sources, power supplies, and connectors. (600) (CMP—18)
Legally Required Standby Systems	Systems that automatically supply power to selected loads during failure of normal power. (CMP—13)
Life Safety Branch	System supplying power to life safety equipment with automatic alternate power connection. (517) (CMP—15)
Lighting Assembly, Cord-and-Plug-Connected	Luminaire for spa, hot tub, or pool installation with transformer. (680) (CMP—17)
Lighting Assembly, Through-Wall	Assembly for installation above grade, through pool wall. (680) (CMP—17)
Lighting Outlet	Outlet for direct connection of lampholder or luminaire. (CMP—18)
Lighting Track	Assembly to support luminaires, repositionable on track. (CMP—18)
Limited Care Facility	Facility for housing individuals who cannot preserve their safety. (CMP—15)
Limited Finishing Workstation	Power-ventilated apparatus for spray application processes. (CMP—14)
Line Isolation Monitor	Test instrument checking impedance from isolated circuit to ground. (517) (CMP—15)
Liquid Immersion «o»	Protection method where equipment is immersed in liquid to prevent ignition. (CMP—14)
Listed	Equipment, materials, or services that meet designated standards. (CMP—1)
Live Parts	Energized conductive components. (CMP—1)
Load Management	Process to limit electrical load through an energy management system. (CMP—12)
Location, Anesthetizing	Space where anesthetic agents are administered. (CMP—15)
Location, Damp	Locations protected from weather, subject to moderate moisture. (CMP—1)
Location, Dry	Locations not subject to dampness or wetness. (CMP—1)
Location, Remote	Location where a production is filmed or recorded. (CMP—15)
Location, Wet	Locations exposed to weather or saturation with water. (CMP—1)
Location, Wet Procedure	Patient care space where procedures are performed under wet conditions. (CMP—15)
Locations, Hazardous (Classified)	Locations with fire or explosion hazards. (CMP—14)
Locations, Unclassified	Locations not classified under specific hazardous zones. (CMP—14)
Long-Time Rating	Rating based on an operating interval of 5 minutes or longer. (660) (CMP—12)
Loudspeaker	Equipment that converts AC electric signals into sound. (640) (CMP—12)
Low-Voltage Contact Limit	Voltage limits for low-voltage contact. (680) (CMP—17)
Low-Voltage Suspended Ceiling Power Distribution	System distributing power through Class 2 supply in suspended ceiling. (393) (CMP—18)
Luminaire	Complete lighting unit with light source and power supply connection. (CMP—18)
Luminaire, Dry-Niche	Luminaire sealed against water entry, installed in pools or spas. (680) (CMP—17)
Luminaire, No-Niche	Luminaire installed above or below water without a niche. (680) (CMP—17)
Luminaire, Wet-Niche	Luminaire surrounded by water in a pool or fountain structure. (680) (CMP—17)