Have you ever wondered what makes those amazing lights so… well amazing? Most people may not realize that light bulbs carry qualities and features which are crucial come decision time. Whether its fluorescent, LED, metal halide or induction each bulb carries 4 characteristics that differentiates them from others.

The four characteristics of light bulbs are:

  • Color Temperature
  • Color Rendering
  • Foot Candles
  • Lumens

Color Temperature: Why does the light feel warm?

When determining which mood you’d like to set in a residential or public space, the color temperature is very important. For example, if you want a more soft or dim lighting in a seating area of a waiting room or want to increase work productivity in an office environment, the CCT (Correlated Color Temperature) would need to be defined.

What are the 4 Characteristics of Light Bulbs?What are the 4 Characteristics of Light Bulbs?

Measured in Kelvins (K) the CCT ranges from 1,000 – 10.000, with the lowest being classified as warm and the highest as cool. For the sake of light bulbs, the color temperature only falls between 2700K to 5000K.

Color Rendering: What does that light make my teeth look yellow?

When it comes to choosing the best lighting source, you may find yourself wondering why that picture you snapped with your camera makes your smile brighter than normal? Well, this is due to the light’s color rendering index (or CRI).

The International Commission on Illumination defines CRI as a measurement of the quality of color light. In other words, how artificial light can enhance or diminish the appearance of an object as seen by the human eye.

Light bulbs are generally given a CRK rating that ranges from 0 (low pressure sodium street lamp) to 100 (incandescent light bulb). The higher the CRI the more clear the visual perception is. ***Bulbs with CRI measurement above 70 are used more in office and residential settings.

What are the 4 Characteristics of Light Bulbs?

Foot Candles: Why are lights placed a particular distance apart in the hallway?

If you’ve walked down a hallway of a commercial business, school or residential space, then you 


may have noticed that the lighting fixtures were installed at a certain height on the wall or ceiling while being set apart by distance. This is referred to as the foot-candle measurement.

By definition, foot-candles are known as a unit of illumination that falls on 1-square foot area at a distance of 1-foot apart.

This is to ensure that the normal fixtures are able to provide the necessary lighting, whether during normal operation or emergency, without any dark spots.

Lumens: Why is the lighting in this place so bright?


You’re at the gym and you notice that your eyes are a bit irritated by the bright illumination that’s’ piercing through your optics. Most people would rather run for cover, however, you’re more interested in why the weight room is seems to reminisce of a tanning bed. Well, chances are that the gym upgraded their lighting with a higher lumen output.

Lumens are defined at the measurement (or distance) of the total amount of visible light emitted by a bulb. Broken down in laymen’s terms, lumens are the amount of light (or brightness) that comes out of the bulb that shines in all directions on a surface. Think is lumens as what pounds are to bananas. 

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