LIGHT POLLUTION

ISSUES AND ANSWERS

Steve Pauley MD

Ketchum, Idaho

http://www.darksky.org

2/3 of the US population

and

1/5 of the world can no longer see the Milky way.

99% of the population in the lower 48 and the EU live in areas where the night sky is above threshold set for polluted status.

The Cost of The Cost of Throwing Away ElectricityThrowing Away Electricity

The USA spends over $1.5 billion per year in energy costs from wasted light.

= 6 million tons of coal or

= 23 million barrels of oil per year

Light Pollution Is the Easiest Type of Pollution to Fix.

Reduce It, Shield It, & Shine It Down.

Light the Subject & Hide the Source.

Follow IESNA rec. levels.

Light PollutionLight Pollution Outdoor lighting currently stands as one of the

most inefficient uses of energy today.

30 to 50% of all light pollution is produced by roadway lighting that shines wasted light upwards and outwards.

Light PollutionLight Pollution

We wouldn’t allow 30 to 50% of water from a hose to escape onto the pavement un-used. We wouldn’t run our electric heaters in winter with the windows wide open.

Light PollutionLight Pollution

Then why do we allow 30 to 50% of light photons from outdoor lighting escape into space?

We throw away electricity.

Three Million Years Three Million Years of Dark Adaptationof Dark Adaptation

The same eyes we have today allowed our ancestors to live and hunt at night by the light of the moon and stars.

Let’s be allowed to use our eyes at night.

Human Eye At Human Eye At NightNight

250 million years ago:

Evolution of the human eye’s binocular vision began with the appearance of mammals

Smaller noses and less sense of smell; Better eyes with acute vision and depth of field

Human Eye At Human Eye At NightNight

Two million years ago:

Early man huddled around the light of fires on the African savanna

500,000 years ago:

Homo erectus used fire to cook food (China digs)

Human Eye At Human Eye At NightNight 150,000 years ago:

Homo sapiens used fire for cooking and warmth. They used the same eyes we have today to navigate, hunt, cook, eat, and give birth under the light of the moon and stars

20,000 years ago:Homo sapiens used shallow stone candles fueled with animal fat and with wicks of plant matter. Stone candles enabled stick figure art work on cave walls (France)

Evolution of Light PollutionEvolution of Light Pollution

3000 BC: first candles

Greeks, Romans through the middle ages: oil lamps

1784: hollow wicks used for brighter light

Early colonists: fish & whale oil lamps

Evolution Of Light PollutionEvolution Of Light Pollution

1800’s: kerosene lamps 1801: first electric lamp -carbon arc

lamp. Sir Humphrey Davy

1879: incandescent lamp. Thomas Edison & Sir Joseph swan

Evolution Of Light PollutionEvolution Of Light Pollution

1930’s: Mercury vapor (terrible beginnings) 1939: Fluorescent 1940: PAR lamps 1950’s: Tungsten Halogen

-------------The End of Night--------------------------------------- 1960’s: Metal Halide and HPS 1980’s Compact fluorescents (good – energy savers) 1990’s Electrodless (Induction) lamps 2000’s: Lighting designers run amok - laser shows; bridge

lighting; tower lighting; beacons on buildings

We have the same eyes now that they had then.

Thomas EdisonThomas Edison

Edison’s electric light in 1879 resulted, over time, in forming an industry dedicated to selling the public the idea that the more outdoor light, the better.

Today’s Lighting IndustryToday’s Lighting Industry

Harsh lighting is sold in the name of “security,” but more often it is used for advertising, and to sell bigger and brighter lighting fixtures.

It has proven to be a visual insult to the human eye, and has gradually stolen the night away.

Space NeedleSeattle, WA

Lightingdesigners runamok

Steve’s Fundamental Laws Steve’s Fundamental Laws of Light Pollutionof Light Pollution

First law:

Without local lighting ordinances, bad lighting gets progressively worse

Second law:

A. Light pollution is directly proportional to improvements in lighting technology, and

B. Inversely proportional to an awareness of the issues at the local level – city planners can reverse the trend

Steve’s Fundamental Laws Steve’s Fundamental Laws of Light Pollutionof Light Pollution

Examples:

Progressive eye insults beginning with incandescent bulbs, then HID lamps, then schemes to light up cities and bridges

Evolution of light pollutionIn Los Angeles 1908-1998

1908

1998

What will we look like in 2098?

TYPES OF LIGHT POLLUTION

GlareLight TrespassSky GlowAir pollutionEnergy wasteConfusion and clutter

The Enemy of Dark SkiesThe Enemy of Dark SkiesIs Horizontal LightIs Horizontal Light

The Battleground for light Pollution Centers on the Fixtures That Shine Light Just a Little Above the Horizon.

This Light Is Scattered the Most.

Types of Light PollutionTypes of Light Pollution

GlareLight that beams directly into your eyefrom an annoying light fixture

Blinding glare: gas stations, theater effect

Disability glare: scattering of light – elderly with cataracts

Discomfort glare: annoyance, fatigue

Light Trespass

When Light Crosses Property Lines

The Spillover of Light Where It’s Unwanted and Unneeded

Light Trespass: a Neighbor’s Unwelcome Light Can Reduce the Value of One’s Property.

Light Trespass

Skyglow lights up birds and planes

Types of Light PollutionTypes of Light Pollution

Air pollution: greenhouse gasses from fossil fuel power plants

Light confusion and clutter: too many

kinds of different fixtures and colors of light

Good on left, bad on right

Gas Stations

Who is “safe” here?

Glare is never good

GLARE

Can you find the “bad guy?”

Glare lighting does notallow the eye to see intothe shadows

This tree is “safe”

The acorn trap

They look their bestin daylight.

Original globes had soft, incandescent lights

Today’s globes andAcorns have glare producingHID lamps (hps, mh)

Globes and acorns light the trees betterthan the ground

Glare from acorn light

No lighting awards hereTurning night into daywhile insulting the eyewith glare

What Is Good Lighting?What Is Good Lighting?

It lights for the human eye using only the amount of light needed (follow the IESNA guidelines).

Good LightingGood Lighting It lights the subject and hides the light

source (lamp).

It provides adequate light for the intended task, but never over lights.

Good LightingGood Lighting

It uses fully shielded light fixtures.

It minimizes adverse impacts (light trespass) on adjacent property.

It uses high efficiency lamps while considering the color and quality as essential design criteria.

Luminance:

The perceived brightness measured in candelas/sq meter.

Illuminance:

The visual effect that luminance produces.Measured in Footcandles = lumens/sq footOr Lux = lumens/sq meter

IlluminanceIlluminance Foot-candles (fc)= lumens / sq foot. We use fc in the USA Lux = lumens/sq meter

A local gas station’s lights peak at 270 fc = over 10,000 times the light from a full moon. The IESNA minimum safe light levels for an urban gas station = 10 fc; rural = 5 fc

Lighting ordinances should specify limits in lumens not watts

Lumens And WattsLumens And Watts A watt = one joule per sec., Or a current of one amp. Under

an electrical pressure of one volt. Idaho Power residential now about 5.7 cents/kwh USA’s avg. Rate = 8 cents/kWh.

A lumen = a unit of luminous flux or a measure of the intrinsic brightness of a lamp. (An isotropic point source of luminous intensity of 1 candela emits one lumen into a unit solid angle of one steradian (sr), or 4 pi lumens on the spherical surface surrounding the point source).

. .

A Light’s Efficiency Is Measured inA Light’s Efficiency Is Measured inLumens Per WattLumens Per Watt

7700 Watt Incandescent Bulb = 1200 Lumens Watt Incandescent Bulb = 1200 Lumens

7070 Watt High Pressure Sodium Lamp = 6300 Lumens Watt High Pressure Sodium Lamp = 6300 Lumens

60 Watt Incandescent Bulb = 60 Watt Incandescent Bulb = 900900 Lumens Lumens

15 Watt Compact Fluorescent Bulb = 15 Watt Compact Fluorescent Bulb = 900900 Lumens Lumens

Lighting Levels Are Best Expressed inLighting Levels Are Best Expressed in Lumens, NotLumens, Not Watts.Watts.

All HID Lamps Today (HPS, LPS, MH, MV) All HID Lamps Today (HPS, LPS, MH, MV) Are Over 1800 LumensAre Over 1800 Lumens

Light Sources, Watts, and Lumens

Source Watts Lumens Life Lu/W

Incandescent 100 1,690 750 hrs 17Tung-Halogen 300 6,000 2,000 20Comp. Fluorescent 26 1,800 10,000 70Merc. Vapor 175 7,900 24,000 45Metal Halide 100 8,075 10,000 81Metal Halide 400 36,000 20,000 90HPS 70 6300 24,000 90HPS 250 26,000 24,000 90LPS 180 33,000 24,000 150

Street lights are on 4100 hrs/year.HPS & LPS lamps will last 5.8 yrs

Pole Heights and Lumen Limits

Pole Height Lumens6ft 400-1000 (Incandescent, PAR,8ft 600-1600 fluorescent, halogen)10ft 1000-200012ft 1600-240016ft 2400-6000 (begin HID lamps)20ft 4000-800024ft 6000-900028ft 8000-1200032ft 9000-2400036ft 12000-2800040ft 16000-32000

Useful Reference Levels for Useful Reference Levels for Foot-candle ValuesFoot-candle Values

1. Full moon .02 fc

2. Living room 10 fc

3. Sitting at my computer 12 fc

4. Schools 7.5 - 30 fc

5. AAA league baseball park 85 fc

6. Today’s gas stations 50 - 270 fc

7. Jewelers counter 400-800 fc

8. Operating table light 490 fc

9. Sunlight 10,000 fc

Native Hog Steelhead -- Steve SmithSalmon River near Stanley April 2000

IESNA =

The Illuminating Engineering Society of North America.

Sets Minimum Foot-candle Levels Needed to Provide for Safety and Security for Specific Situations, I.E. Parking Lots, Walkways, Roadways, Gas Stations, Etc.

IESNA

RecommendedPractices (RP)Publications

Full Cutoff ShieldingFull Cutoff Shielding

Essential remedy for glare and skyglow

No light rays from the fixture go above the horizontal

At least 90 percent of light is blocked in the near-sideways range from 0 to 20 degrees below the horizontal

Typical 175 w mvunshielded yard light

$35 Sky Capshield placed to cut glare, trespass, & skyglow

Recessed canopy lights

Aluminum shielding over canopy lights

Security IssuesSecurity Issues

More than meetsthe eye i.e. not justglare lighting

More light does not =better security.

Security =effective, non-glare lighting.

SECURITY

Lighting and SafetyLighting and Safety

More light does not equate to better, safer light.

You can have less but more efficient lighting and not compromise safety at all.

Glare From Poor Lighting Allows Criminals to Hide in Dark Shadows. Shielded, Non Glare Lighting Allows One to See in the Shadows.

We’re Not Saying Let’s Turn Out All the Lights.

Lighting for Security Means Effective, Shielded, Non Glare Lighting That Meets the IESNA Minimum Light Levels.

Lighting and CrimeLighting and Crime

A complex issue

No study proves that more light decreases crime

More light does give people the feeling of more security

Lighting and CrimeLighting and Crime

Most crimes take place during the day

Two congressional crime task forces (1979 & 1997) found no relationship between lighting and crime

“There are simply no good scientific studies that convincingly show the relationship between lighting and crime.” - (Ref - IDA information sheet 42; 4/98)

Crime Deterrents at Night:Crime Deterrents at Night:

Best: dog (pit bull?)

Next best: shielded, infrared motion detector flood lights combined with a video camera. Some schools have gone dark, used this system, and vandalism has decreased

Total solar eclipseZimbabweJune 21, 2001

LIGHTNG ORDINANCES

Why an Ordinance? • Enhances the quality of life for all. • Sets a uniform code for all outdoor lighting.

Architects don’t need to guess whatwhat you want – saves them time andthe client’s $$$.

• Enhances safety and security by reducing glare• Reduces light pollution.

• Allows redress for citizens exposed to a neighbor’s bad light

• It can lead to cost savings

Without Lighting Ordinances, the Bad Practices of the Last 100 Years Will Simply Escalate in the Name of Economic Progress and “Safety.”

12 Points For A Good 12 Points For A Good Lighting Ordinance Lighting Ordinance

1. Promote good lighting without compromising safety or security.

2. Convert street lights to full cut-off fixtures. That can result in reduced lumen levels, lower wattage lamps, and a savings in electric bills.Can reflectors be used instead of street lights?

3. Address glare from unshielded flood lights.

4. Address light trespass. Use Kennebunkport formula, not light police.

H = 3 + D/3

5. Require that only the minimum IESNA lighting levels be reached for a given situation – follow the IESNA RP guidelines

6. Prohibit upward lighting of all types

7. Require signs to lighted from the top down.7. Require signs to lighted from the top down.

8. Educate all parties on what good lighting should be.8. Educate all parties on what good lighting should be.

9. Promote the use of motion detector lighting and timing 9. Promote the use of motion detector lighting and timing devices. Suggest all non essential lighting be turned off by 11 devices. Suggest all non essential lighting be turned off by 11 PM. PM.

10. Allow local P & Z’s to require lighting for the human eye 10. Allow local P & Z’s to require lighting for the human eye and safety using IESNA minimums, rather than up lighting for and safety using IESNA minimums, rather than up lighting for trees, rocks, and buildings. Down light flag poles.trees, rocks, and buildings. Down light flag poles.

11. Never allow for more lighting than what is really needed. 11. Never allow for more lighting than what is really needed. Make lighting controlled, efficient, and effective.Make lighting controlled, efficient, and effective.

12. Enforce all lighting ordinances with 12. Enforce all lighting ordinances with finesfines..

Cost of RetrofittingCost of Retrofitting

Often recovered in three years. Depends on formula your utility company uses to bill for light pole maintenance.

San Diego is saving $3 million a year in power bills by retrofitting its street light fixtures to LPS.

Other BenefitsOther Benefits

Looks pleasant. Smooth, uniform illumination. Reduced glare is safer for motorists.

You can see pedestrians and objects more easily.

The elderly with cataracts are less affected by glare and will be safer drivers.

Light at Night and Light at Night and Human HealthHuman Health

Researchers have shown a definite link between exposure to light at night and lower melatonin levels – in all living things.

Light at Night and Light at Night and Human HealthHuman Health

Exposure to light at night = decreased melatonin levels. Part of our circadian system of light-dark rhythms.

Nightly melatonin production by the pineal gland is needed for good health.

• 5 Retrospective Studies Totally blind women with no light perception have a

roughly 30% less incidence of breast cancer.

Human breast cancer cells implanted in rats grow fasterwhen the rats are exposed to light at night. Melatonin levels

are reduced by exposure to light at night.

• Breast cancer rates are highest in industrialized nations where night lighting levels are also the highest.

Researchers are pursuing these connections.No cause and effect can be made now.

• Nightly melatonin production in humans is beneficial toour health. Light exposure interferes with that.

“Light is a drug and that by abusing it, we risk

imperiling our health.”

Dr. Russell J. Reiter

University of Texas Health Science Center,

San Antonio, TX

Everybody Wins With Everybody Wins With Good LightingGood Lighting

Enhances the quality of life for all

No compromise to safety or security

Can save money

Less pollution

Everybody Wins With Everybody Wins With Good LightingGood Lighting

Less glare, light trespass & sky glow

Restores dark skies for stargazing

Prevents the pervasive spread of light pollution

Preserves the night skies for our children

Steve’s Modification of the Iroquois’Steve’s Modification of the Iroquois’ 7 Generations Principle7 Generations Principle

We should not pass through this life just to make our own lives We should not pass through this life just to make our own lives easier at the expense of our natural world and futureeasier at the expense of our natural world and future

generations of humans.generations of humans.

We are OF this planet, not unique to it. We are charged with acting We are OF this planet, not unique to it. We are charged with acting as stewards of our natural world.as stewards of our natural world.

We must take actions today that better the lives of those who, We must take actions today that better the lives of those who, in 110 years, replace today’s entire population on earth.in 110 years, replace today’s entire population on earth.

Each of us can do just one small thing to better the lives of Each of us can do just one small thing to better the lives of those who will be here 110 years from now –i.e. preserve the night sky.those who will be here 110 years from now –i.e. preserve the night sky.

Ketchum Dark Sky Ordinance- 1999 Incandescent(w)Up to 260 lumens (20w) May be unshielded

260 – 1000 lumens (20-60w) No bulb showing; opaque top

1000 – 1800 lumens (60-120w) = *Floods

0ver 1800 lumens Must be full cutoff fixtures with no (all HID lamps) light above the horizontal----------------------------------------------------------------------------*Floods: Lights from 1000 - 1800 lumens: Must have shielding and opening may not tilt upwards more than 25 degrees from horizontal.Timers and motion sensors are encouraged.Motion sensors must go off in 5 minutes.

Ketchum Lights

In Sept. 2001, Idaho Power completed the retrofit ofall drop lens street lights to these fco lights.

This has reduced glare, sky glow and light trespass without compromising safety.

Old drop lens light

Guardco Lights

Ketchum FCO Parking Lot - Metal HalideGuardco Lights

Good FCO Lighting In All Places

There are exceptions

Overkill – too much full cutoff lighting

Total Overkill. These should be compact fluorescentsAnd only 3 per side of the bldg.

This bldg. has 15 50 watt hps at 4000 lumens each,21 ft apart and 9 ft high. Ridiculous lighting.

15 50watt hpslamps 10 ft high,4000 lumens each,21 ft apart.

60,000 lumens oflight surrounding thebldg.

Overkill

Unfortunately this is legal underthe Ketchum Ordinance since these are all fco lamps.

Overkill

Perfect Lighting

Bad Wall Pack

Better Wall Light

Better Wall Light

Ketchum Post Office

Back lit sign with too muchwhite. Neighbors complained.

For most business signlighting, a down-shieldedlight under 1800 lumens isall that’s needed.

These quartz-halogen floods are not shielded,are over 1800 lumens, and therefore illegal

Good FCO Lights

Opaque cover diffuseslight better

FCO lights at entry

An elementary school parking lot withno lights. No problems.

29 inch brownSilver CreekDry Fly6-21-92

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