Light Pollution and the IES

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Light Pollution and the IES
IESNA/IDA Model Lighting Ordinance
Part 1 The View of an Astronomer
Dan Caton
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What we will look at

• Why protect the sky?
• The light pollution issuea brief primer on sky
  glow, glare and light trespass
• The need for design
• A brief history of the MLO (and why I gave up on
  it)
• Eric Gibson does the numbers

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Light our shared interest
What you do
What I do
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Another shared interest
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My Concern ASUs Dark Sky Observatory
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100,000 hobbyists
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Everyman
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Just as important
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Light Pollution and the IES
Light Pollution the loss of the night sky
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The basic problem Sky Glow

• Light from fixtures reflects off particles in the
  skySky Glow.
• Large cities visible from tens of miles.
• The stars are not brighter in the countrythe sky
  is darker!
• A worse problem here in the east, due to higher
  humidity levels than out west.

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Our Global Problem
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Light Made in the USA
1 G / year of wasted electricity
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Whats Wrong With this Picture?
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Closer to home
You are here!
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Boone 40 years ago
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today
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Charlotte
Courtesy Spencer Rackley
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Light Pollution Causes

• Poor fixture design
• Lack of shielding
• Over-lighting
• Poor installation
• Market pressure
• Lets look at a few specific problems

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Floodlights

• Almost horizontal
• No shielding
• At night

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Typical fast-food lighting

• Discomfort glare, bordering on disability glare
• Light trespass onto adjacent properties, roadway
  drivers
• Contributes to sky glow

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Better Full Cut Off
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Even Better!

• Van Goghs Café Terrace at Night,1888
• Experience at Tweetsie.
• Result from California study reduce glare and
  you can reduce the overall lighting level

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Roadway lighting-overhead glare
Majority of thelight budget? (Note MLO does
not cover)
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Sag-Lens Cobra heads

• Glaring to driver
• Light polluting

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Better, FCO Fixtures

• No light above horizon
• Non-glaring to drivers, too!
• May require more poles per milebut could we get
  the DOT to specify FCO?
• Progress Energy uses on all new roadway now
• And at night

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(No Transcript)
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Car Sales Lots

• Often grossly overlit
• This one at 60-110 Fc on lot, 65 on road
• Can be done nicely

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like this (Tampa)
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Wall Packs

• One of the worst fixtures for pollution as well
  as glare (or even for its intended purpose!)
• Are available in FCO
• What is the point of these? ?

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I will give you architecture
Would be allowed under MLO
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Why shown in day?
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Ever notice?
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Bad area/security lighting
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Health concerns

• Baby sea turtles attracted to street light
• Cancer and melatonin production in people

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Solution put a cap on it

• New GE SkyGard shown here. Hubbell, too
• Guaranteed to 100 mph, tested to 120
• Why not the default for new orders?
• Reduce lamp wattage, with light saved

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Gas Station Canopies
This about 85 fc several times IES RP
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Sports lighting

• Often done poorly with lots of light pollution,
  light trespass, and glare (as baseball fans
  know).
• Can be done better as shown here, using fixtures
  like Muscos shown here

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The Model Lighting Ordinance

• Began evolution circa 2000? Existing IDA
  Lighting Code Handbook long and tedious.
• Jim Benyas paper at 2001 IDA Meeting, A
  Proposal to Establish Inter-Organizational
  Standards for Outdoor Lighting. Lets Do it!
• MLO Working Group met at 2002 Tucson IDA Meeting
  and discussed basics, logistics. Hoped to roll
  out MLO 1.0 at Fall 2002 Boston IDA meeting.
  Members were common with IESNA Outdoor Lighting
  Committee, chaired at that time by Nancy Clanton.
• Draft version (2004.1) circulated, stirring
  controversies about closeness to industry, watts
  vs. lumens, lumens per acre, etc.
• MLO plods along today, cards held close. Based
  on lighting zones with different specifications
  for each.
• I have been less concerned since the MLO in any
  of its incarnations is too complicated for small
  communities like Boone. Besides, I was tired of
  waiting for it!

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Small Town Approach Boone

• Commercial only, at this point.
• Go for light control as the main theme (FCO
  required).
• Floods allowed but must be shielded.
• Gas station canopies must meet 35 fc limit within
  7 years. All other lighting grandfathered in
  but must be changed if renovated.
• Sports lighting must have light control package.
• Minimum/maximum table in footcandles (easy
  enforcement).
• Lighting plan required, including a 10' x 10'
  illuminance grid (point-by-point) of maintained
  footcandles overlaid on the site plan, which
  demonstrates compliance with lighting standards
  specified.
• Effective 1/1/2006. We will see how it works.
• Admitted problem with this approach designers
  face different ordinances in different towns.

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Summarizing

• Light pollution almost always caused by
  luminaires and installation techniques that do
  not do their task well.
• We can all work toward better lighting and (thus)
  darker, starry skies.
• Ordinances should cause lighting to be designed
  which is good for all of us.
• Thank you for your time and attention.
• www.darksky.org and www.ncdarksky.org
• dan_at_caton.name
• www.dan.caton.name