Lighting Guide

Choose Lighting With Confidence

Three things decide how your space looks and how safe it is: color temperature, color rendering and safety listing. Here is what each one means in plain words, and how to choose.

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Color TemperatureWarm or cool white, measured in Kelvin (K).

Color Rendering (CRI)How true colors look, on a scale of 0 to 100.

UL ListingIndependent safety testing that the electrical code requires.

Step 1

Color Temperature, Measured In Kelvin

Color temperature describes how warm or cool white light looks. It is written as a number followed by K, for Kelvin. The same room can feel cozy, neutral or bright and crisp depending on this one number.

Lower number, warmer light. 2700K glows amber like a classic bulb. 5000K looks like bright daylight.
Keep one color per room. Mixing warm and cool fixtures makes walls look patchy.
Tunable white changes with you. Warm in the evening, crisp during work hours, from a wall control or app.

Same Room, Five Color TemperaturesLeft to right: 2700K to 5000K

2700KSoft White

Cozy And Inviting

Candle-warm, like a classic incandescent bulb.

Bedrooms and living rooms
Dining rooms and restaurants
Warm woods and gold

3000KBright White

Warm And Welcoming

Still warm, a little crisper and cleaner.

Kitchens and bathrooms
Entries and hallways
Gold and warm-colored gems

3500KTrue White

Balanced And Natural

Neither warm nor cool, easy on the eyes.

Home offices
Boutiques and showrooms
Spaces used day and night

4000KCool White

Clean And Crisp

Bright and alert, with a fresh look.

Garages, laundry and workshops
Offices and stores
Cases with gold and white metals

5000KDay White

Bright Daylight

Very clear, for seeing fine detail.

Task and work areas
Warehouses and showrooms
Diamonds, platinum and silver

Display And Jewelry Tip

3000K: gold, rubies, garnets and citrine
4000K–5000K: gold and white metals in one case
5000K: platinum and diamonds
6000K: diamonds and silver, with icy sparkle

Step 2

Color Rendering Index (CRI)

CRI tells you how true colors look under a light, on a scale from 0 to 100. A score of 100 matches the reference light, such as daylight or a classic incandescent bulb. The higher the number, the more natural skin, food, wood, fabric and stone look.

The headline number (Ra) is an average of eight soft test colors, R1 to R8.
R9 measures strong red. It drives how skin, wood, food and rubies look, and it is not part of the average, so check it on the spec sheet.
ENERGY STAR's minimum for LED lamps is CRI 80 with R9 above zero. For homes and displays, aim higher.

High CRI 95 And Up

Low CRI Around 70

Illustration of how colors fade and shift under low-CRI light. R9, strong red, is outlined.

80+

Standard

Fine where color matters less.

Closets and storage
Garages and utility rooms
Hallways

90+

Premium

When every detail has to look right.

Jewelry and art displays
Vanities and makeup areas
Galleries, photography and showrooms

Step 3

Why Lighting Should Be UL Listed

A UL Listed mark means an independent, OSHA-recognized lab tested the complete product to published safety standards, such as UL 1598 for light fixtures and UL 8750 for LED equipment, and keeps checking the factory that makes it.

Fire And Shock Protection

Wiring, drivers, heat and enclosures are tested so the fixture does not overheat, short out or expose live parts in normal use.

Required By Electrical Code

The National Electrical Code (NEC 410.6) requires every light fixture, lampholder and retrofit kit to be listed. Low-voltage systems of 30 volts or less must be listed too (NEC 411.3).

Passes Inspection

Inspectors look for the listing mark. Unlisted fixtures can fail inspection, delay permits and hold up a move-in or store opening.

Protects Insurance And Warranty

After a fire or damage claim, an insurer may ask whether the products were listed. Listed products help you avoid a dispute.

Factory Follow-Up Checks

The lab keeps inspecting the factory, so products made later still match the sample that passed testing.

UL Listed

The complete product was tested as a whole and is ready to install.

Look For This

UL Recognized

Only a part inside a product, such as a driver, was tested. It does not make the finished fixture listed.

Part Only

ETL Or CSA Listed

Another OSHA-recognized lab tested it to the same UL standards. Inspectors accept it the same way.

Also Accepted

How To Check A Listing

Find the mark on the product label, not just on the box.
Note the file number printed with the mark.
Look it up in UL Product iQ or the listing lab's online directory.
Ask us for the spec sheet and listing of any product we quote.

Watch For Unlisted Or Fake Marks

Some low-cost LED strips and power supplies sold online carry no listing, a sticker with no file number, or only a Recognized part mark. If a price looks too good, check it before it goes in your wall or ceiling.

Try It Yourself

Compare Every Setting In Light Lab

Slide from warm to cool white, switch to RGBW color, change brightness and beam angle, then watch metals, backlit stone or a photo of your own room respond.