Lighting Stores Industry Terminology

0-10V Dimming

An analog control method using two low-voltage wires to vary light output between about 10 V (full bright) and 0 V (minimum). Common in commercial LED fixtures and controls.

Is this high-bay 0-10V dimmable, with purple/gray leads?; Use a 0-10V wall control and a separate relay for on/off.; The driver sinks current from 10 V (100%) down to ~1 V (low light).

A19 Lamp

A common household bulb shape. “A” means arbitrary shape; “19” means 19 eighths of an inch in diameter (~2.375 inches). Often LED replacements for legacy incandescent.

Replace the old bulb with an A19, 2700K, 800 lm.; The A19 refers to shape/size, not base—this one is E26.; For enclosed fixtures, choose an A19 rated for enclosed use.

ADA Compliant

Refers to Americans with Disabilities Act clearances; for wall luminaires in corridors, projection typically must be ≤4 inches from the wall between 27 and 80 inches above finished floor.

Choose an ADA sconce that projects ≤4 inches for the corridor.; This fixture is not ADA because it sticks out 5 inches at 72 inches AFF.; Filter for ADA-compliant wall lights in tight hallways.

Ambient Lighting

The general, overall illumination in a space that provides uniform light levels, as opposed to focused task or accent lighting.

We have task lights but need better ambient fill.; Aim for 20–30 foot-candles of ambient light in living areas.; Layer ambient, task, and accent lighting for balance.

Average Order Value (AOV)

A retail metric: total revenue divided by number of orders. Indicates how much customers spend on average per purchase.

Our AOV rose from $145 to $165 after bundling dimmers.; Cross-selling lamps with fixtures boosts AOV.; Track AOV by channel—showroom vs. e-commerce.

Beam Angle

The angular spread of a light beam, usually measured at the points where intensity falls to 50% of center beam candlepower; defines spot vs. flood distribution.

Use a 15° spot on the sculpture, 40° flood for the wall wash.; PAR38 comes in 10°, 25°, and 40° beam options.; Narrow beams increase center-beam candlepower.

CCT (Correlated Color Temperature)

A measure (in kelvins) describing the appearance of white light—warm (2700–3000K), neutral (3500–4000K), or cool (5000K+).

Warm dining at 2700K; cool office at 4000K.; Offer tunable CCT from 2700–6500K.; Title 24 JA8 may prefer ≤3000K in some spaces.

CRI (Color Rendering Index)

An index (0–100) indicating how accurately a light source renders colors compared to a reference. 80+ is standard; 90+ is preferred for high-fidelity color.

Choose CRI 90+ for kitchens; ask about R9 values.; This lamp’s CRI 80 is fine for back-of-house.; High CRI boosts merchandise appeal in showrooms.

Conversion Rate

Retail metric: the percentage of visitors who make a purchase. Calculated as orders divided by total visits or leads.

Showroom conversion hit 38% after the weekend event.; Improve PDPs to raise online conversion.; Sampling fixtures at home increased close rate.

Cut Sheet (Spec Sheet)

A product’s technical datasheet listing features, ratings, dimensions, photometric data, certifications, and installation notes.

Download the cut sheet for dimensions and photometrics.; The spec sheet shows CCT, CRI, LM-79 data, and warranty.; We’ll attach the cut sheet to the quote.

DALI (Digital Addressable Lighting Interface)

A standardized digital lighting-control protocol enabling addressable fixtures, groups, scenes, and bidirectional communication.

Program scenes over DALI for the office.; These drivers are DALI-2 certified.; Consider D4i drivers for luminaire-level sensing.

Dark Sky Compliant

Fixtures that minimize light pollution—typically full cut-off optics, low uplight, controlled glare, and warm CCT, often meeting IDA guidelines.

Select fully shielded, ≤3000K fixtures for dark-sky.; IDA-approved wall packs reduce uplight and glare.; Check BUG rating to limit spill.

Daylight Harvesting

Control strategy that uses photosensors to automatically reduce electric lighting when sufficient daylight is present, maintaining target light levels.

Photosensors dim rows near windows.; Daylight zones tied to 0-10V drivers.; Saves energy and helps meet code.

DLC (DesignLights Consortium)

A certification for commercial/industrial products meeting performance criteria. Many utilities require DLC listing for rebates (Standard or Premium tiers).

DLC Premium qualifies for higher rebates.; Search the DLC QPL for approved troffers.; Spec DLC-listed exterior area lights.

Driver (LED Driver)

Electronic device providing regulated power to LEDs (constant current or voltage), often with integrated dimming and protection features.

Use a constant-current 700 mA driver.; Is the driver TRIAC- or 0-10V-dimmable?; Remote vs. integral driver affects junction box space.

E26 Base

The standard medium screw base (26 mm) for many North American lamps. Distinct from E12 (candelabra) and E39 (mogul).

Medium E26 base fits most US sockets.; This A19 uses E26; the chandelier uses E12.; Check base type before recommending.

Efficacy (Lumens per Watt)

A measure of how efficiently a light source converts power into light output, expressed as lumens per watt (lm/W).

This downlight is 110 lm/W.; Higher efficacy reduces operating cost.; Compare efficacy to gauge energy savings.

Energy Star

EPA program that certifies energy-efficient products, heavily used in residential lighting and utility incentive programs.

ENERGY STAR A19s qualify for residential rebates.; Use the product finder to verify listing.; Good for consumer trust and warranty expectations.

Flicker (Flicker Percentage/Index)

Temporal light modulation that can cause visual discomfort or artifacts. Quantified by percent flicker or flicker index; affected by driver quality and dimmer compatibility.

Specify low-flicker drivers for offices.; This lamp flickers on TRIAC—try an ELV dimmer.; IEEE 1789 guidance helps evaluate risk.

Foot-candle

A unit of illuminance equal to one lumen per square foot; common in North American lighting design and codes.

Target 30 fc on the workplane.; 1 fc ≈ 10.76 lux.; Measure with a light meter during commissioning.

GMROI (Gross Margin Return on Inventory)

Retail KPI: gross margin dollars divided by average inventory cost. Shows how efficiently inventory generates profit.

Our GMROI improved after rationalizing SKUs.; Focus on lines with GMROI > 2.5.; DLC rebates boosted GMROI on troffers.

HCL (Human-Centric Lighting)

Design approach aligning light intensity, spectrum, and timing to support visual comfort and human circadian/wellness needs.

Program warmer CCT in the evening.; HCL package combines tunable white and controls.; Sell HCL as an upsell for wellness projects.

IC-Rated (Insulation Contact Rated)

A recessed luminaire or housing rated for direct contact with insulation without risk of overheating.

Use IC-rated cans under attic insulation.; IC/AT housing helps with energy code.; Non-IC recessed fixtures require clearance.

IES File (Photometric Data)

A standard photometric file format (.ies) defined by IES for fixture light distribution data used in lighting calculations and renderings.

Import the .ies into AGi32 for layouts.; Ask the vendor for an IES file, not just the cut sheet.; The IES shows distribution and CBCP.

IP Rating (Ingress Protection)

International code indicating protection against solids and liquids (e.g., IP65 = dust tight and protected against water jets).

IP65 for wet locations; IP20 for dry interiors.; Landscape spots need IP67.; Bathroom fixtures: check IP44 splash protection.

Lead Time

The time from placing a purchase order to receiving goods. Critical for project schedules and customer expectations.

Custom pendants have 6–8 week lead times.; Ask about quick-ship options to meet move-in.; Port delays extended lead times this quarter.

LM-79

IES testing standard for electrical and photometric measurements of LED luminaires and lamps (e.g., lumens, efficacy, distribution).

Request LM-79 reports for lumen and efficacy.; Photometry was done per LM-79.; Use LM-79 for apples-to-apples comparisons.

LM-80

IES standard specifying how to measure lumen maintenance of LED packages, arrays, or modules over time.

We have LM-80 data at 55/85°C for 10,000 hours.; LM-80 supports TM-21 projections.; Check that the LED package passed LM-80.

Lumen

A unit of luminous flux; the total amount of visible light emitted by a source.

This A19 produces 800 lumens.; Compare lumens, not watts.; Higher lumen output for high ceilings.

MAP (Minimum Advertised Price)

A manufacturer policy that sets the lowest price a retailer may advertise. Common in branded lighting to protect margins.

We can’t post below MAP online.; Holiday promo approved at MAP minus 10% rebate.; MAP violations risk losing the line.

Omnichannel Retail

Integrated retailing across showroom, e-commerce, marketplaces, and fulfillment options, providing a seamless customer experience.

Sync inventory for online and showroom availability.; Offer BOPIS and BORIS to lift conversion.; Unified pricing and promos across channels.

PAR38 Lamp

A reflector lamp type (Parabolic Aluminized Reflector) with a diameter of 38 eighths of an inch (~4.75 inches), common for spot/flood applications.

Use PAR38 floods for the driveway.; Offer 25° spot or 40° flood beams.; Select 3000K, 90 CRI for exterior accents.

Planogram

A visual merchandising layout that specifies product placement on shelves or displays to maximize sales and shopping ease.

Reflow the bulb wall by base type and CCT.; Our planogram dedicates 4 feet to smart lamps.; Eye-level shelves for high-margin fixtures.

Rebate (Utility)

Incentive from utilities for qualified energy-efficient products (often DLC or ENERGY STAR), reducing customer net cost.

This DLC Premium high-bay earns a $80 rebate.; Pre-approve with the utility before ordering.; Bundle paperwork with LM-79 and cut sheet.

Retrofit Kit

A set of components designed to convert an existing fixture to LED while reusing parts of the original luminaire or housing.

Convert 2x4 troffers with LED kits.; UL1598C retrofit preserves housing.; Great for HID wall packs going to LED.

RMA (Return Merchandise Authorization)

The formal process and authorization number for returning products to a vendor for credit, repair, or replacement.

Open an RMA for the defective driver.; RMA requires proof of purchase and photos.; Await RMA number before shipping back.

SKU (Stock Keeping Unit)

A unique identifier for each product variant in inventory, ordering, and POS systems.

Create a unique SKU per CCT/finish.; Bundle dimmer + bulbs under a new SKU.; Audit duplicate SKUs to clean the catalog.

Smart Lighting

Networked or app-enabled lighting that supports automation, voice control, scenes, and integration with smart-home platforms.

Control scenes via app and voice.; Bridge Zigbee bulbs to the Wi‑Fi hub.; Upsell smart dimmers with tunable lamps.

Solid-State Lighting (SSL)

Lighting that uses semiconductors (LED, OLED) instead of filaments or gas discharge. Enables high efficacy and advanced controls.

SSL has displaced most HID in retail.; Discuss SSL optics vs. legacy reflectors.; SSL enables compact, efficient luminaires.

T8 Lamp

A tubular lamp with a diameter of 8 eighths of an inch (1 inch). Now commonly LED replacements: Type A (ballast), Type B (ballast-bypass), Type C (external driver).

Replace T8 fluorescents with Type B LED.; Choose ballast-compatible (Type A) for quick swaps.; Confirm single- or double-ended wiring.

Title 24 (JA8)

California Energy Code (Part 6) requirements; JA8 covers high-efficacy, quality requirements for residential luminaires and lamps.

JA8-listed lamps for California residential.; Use 2700–3000K, high CRI for compliance.; Check JA8 marking on the package.

TM-21

IES technical method for projecting long-term LED lumen maintenance using LM-80 test data.

Projected L70 at 50,000 hours via TM-21.; Use LM-80 data to run TM-21 projections.; Compare L90 values across vendors.

TRIAC Dimming

Phase-cut (forward) line-voltage dimming using a TRIAC-based wall dimmer. Common in residential; compatibility with LED drivers varies.

Forward-phase dimmer caused low-end flicker.; Specify TRIAC-compatible drivers for retrofit.; Try an ELV dimmer if buzzing persists.

Tunable White

Ability to adjust a fixture’s CCT dynamically (and sometimes intensity) to create different ambiences or support circadian goals.

Program 2700K morning, 3500K midday, 3000K evening.; Pair tunable downlights with DALI DT8 controls.; Sell as part of HCL packages.

UGR (Unified Glare Rating)

A metric for evaluating discomfort glare from luminaires in a given layout. Lower values indicate less perceived glare.

Keep UGR < 19 for open office lighting.; Lenses and louvers help reduce UGR.; Photometric software can calculate UGR.

UL Listed

Underwriters Laboratories safety certification indicating a product meets electrical/fire safety standards for the intended environment (dry, damp, wet).

This fixture is UL Listed for wet locations.; UL vs. ETL—both are NRTL safety marks.; Verify UL labels for inspection.

Warranty

Manufacturer’s promise to repair or replace products within a period (often 3–10 years for LED), subject to terms and exclusions.

5-year limited warranty on driver and LEDs.; Prorated terms after year three.; Register serials to streamline claims.

Wattage Equivalency

A marketing/benchmark reference that compares LED light output to legacy lamp wattages. Should be validated by lumens and application.

9W LED ≈ 60W incandescent.; Replace 250W metal halide with 100W LED high-bay.; Explain that equivalency also depends on beam and optics.

Zigbee

A low-power mesh networking protocol used by many smart bulbs and switches for reliable, scalable control via hubs/gateways.

Zigbee 3.0 bulbs join the mesh via a hub.; Bridge Zigbee to Matter controllers.; Use Zigbee for large smart-home lamp networks.

Z-Wave

A sub‑GHz mesh protocol for smart-home devices (including lighting controls) with good range and interoperability via certified hubs.

Z-Wave dimmers avoid 2.4 GHz congestion.; Pair Z-Wave switches with a compatible hub.; Check Z-Wave Plus for extended range.