Lighting Facts

Incandescent Lighting

The standare household light is called incandescent.  It is the most comfortable light for your eyes due to a warm temperature and broad spectrum (CRI = 100).

However incandescent bulbs are not efficient at producing lumens.  Much of the electricity that is used by an incandescent bulb is released as heat.  Not such a bad thing in Flagstaff, especially in winter months, but terrible in warmer climates.  The heat can also slowly cause damage to wiring depending on the fixture.

LED lighting

LED lighting is great for most purposes.  Look for warm white versions with a high CRI number (over 90) for indoor use.

Municipalities and businesses should avoid using broad spectrum (high CRI) cool white LED lights outdoors. Even though they are energy efficient, they contribute significantly to light pollution due to their relatively broad spectrum light compared to traditional street lights.  See this article.  The cool daylight temperature can lead to sleep problems for humans and animals.  More about the problems of LED lighting outdoors.  For personal residences they can be better than standard incandescent bulbs as long as the total lumens do not increase.  One option is to use amber color LEDs for all exterior light purposes. The dark sky lighting practices should be followed. Northern Arizona jurisdictions such as Flagstaff, Sedona and Coconino County all have dark sky lighting ordinances. 

Fluorescent Lighting

Fluorescent lighting is generally a bad choice, due to mercury content, poor light quality and inefficiency when switched often.

If you do need fluorescent tube lighting, consider one of today's more efficient bulbs, including the T-5 and T-8 bulbs which contain lower levels of mercury compared to previous generation fluorescent bulbs. 

Not all fluorescent lights are created equal.  Some bulbs are more efficient than others, producing more lumens. Also different models carry a higher CRI number.  Basically the higher the CRI number, the more realistic colors the light will produce.

All fluorescents are by nature strobe lights.  You eyes don't see it, but fluorescent bulbs strobe at a rate of 60 times per minute.  This is due to their being powered by A/C electricity.  Alternating Current electricity in the U.S.A. is 60 Hertz.  This basically means the electricity changes flow 60 times a second.  This change causes fluorescent bulbs to dim and brighten 60 times every second.  Too fast for the eye to see, but easy to catch on video.  If you ever capture a video under fluorescent lights at a shutter speed that is not a multiple of 60, you will see the picture dim and brighten as the video plays.

Fluorescent lights also have the disadvantage of slowly turning on and slowly reaching full brightness after being turned on, even with new modern ballasts.  Fluorescents bulbs also use a lot of energy every time they are switched on. 

Recycling Fluorescent Bulbs

All Fluorescents should be recycled due to their mercury content. CFLs can generally be recycled for free at home centers.  Tube fluorescents cost about $0.50 per foot to recycle. 

If your tube fluorescent bulbs are burning out, consider having us replace them with LED tubes instead.  LED tubes produce better light, at a cheaper cost and don't contain mercury.  We can haul off your old fluorescent bulbs and dispose of them for you. 

Lumens, Temperature, and CRI

Lumens

Lumens are the measure of light output - how bright a light is.  A 100-watt light bulb produces 1600 lumens.  A 26 watt CFL and a 18 watt LED also produce 1600 lumens.  It is easy to see that an LED light uses 82% less electricity to produce the same amount of light as standard 100-watt light bulb.  Standard (incandescent) light bulbs spend many of their watts in producing heat.  Not such a bad thing in cold climates!  Standard light bulbs have some advantages such as producing warmer light and more realistic light. Keep reading...

Color Temperature

Color Temperature refers to how warm or cool the light appears.  Higher numbers are cooler.  Incandescent bulbs are 2700k (warm).  Candles are 1700 (very warm).

For indoor lighting we use and recommend lighting in the 2700k-3000k range.  This is the warm light range which is very comfortable to the human eye. CFLs (compact fluorescent lamps) and LEDs can be found in several color temperatures including 'warm white' which is similar to incandescent bulbs, but they still lack the ability to illuminate color as well.

Sunlight is very cool at about 6500k depending on weather conditions.  Very cool light has been shown to disturb sleeping patterns.  (This is another reason not to stare at computers or cell phones before bed - 6500k).   Several cities, including L.A., Boston and New York have made the mistake of installing cool temperature LED bulbs in their street lights.  This has created problems for both humans and animals regarding sleep patterns due to the daylight type light these bulbs produce.

CRI - Color Rendering Index

CRI is a measure on a scale of 0-100 of how well a light source renders colors. Sunlight, candles and incandescent bulbs all score 100.  Generally speaking closer to 100 is better for most applications except night-time exterior lighting. High quality fluorescents and LEDs both typically score in the 80s.  Cheaper fluorescents will often score in the 60s. 

New high CRI LED street lights are doing more than just causing sleep problems due to their cool light color, they are also increasing light pollution due to their high CRI ratings.  The traditional yellowish street lights we are accustomed to seeing have a very low CRI numbers, which basically amounts to less light reflecting off the ground and going into the sky.  Astronomers prefer low CRI numbers for commercial exterior lighting as it is less disruptive for their observations.  Anyone who loves seeing the stars at night should oppose the use of broad spectrum (high CRI) lighting in street lights.

Exterior Lighting

When shopping for exterior lights for your home, avoid the big box stores because most of the fixtures they offer are NOT code compliant and are generally illegal for exterior use in Flagstaff, Sedona and Coconino County.  They are also usually made in China.

Nitro Electric recommends buying Made in America light fixtures.  The following companies offer Made in the U.S.A. exterior lights, which are also Dark Sky Compliant:

Steel Lighting Company - Lamps Expo - Avalanche Ranch Lighting - Barn Light Electric Company

Whatever your lighting needs, let us help you recommending and installing the best lighting for your home or business.

Contact us today at Nitro Electric.