Designing Public Lighting for the Public: The AMA Design Guide by Bob Parks

4. Why We Light
• To Improve Visibility
• To Extend the Day
• To Enhance Commerce
• To “Feel Safe”
• Fear of Litigation
• Primal Fear of the Dark

5. Lighting and Safety
• Does more Light = More Safety?
• No evidence to support this assumption
• Street Lighting increases “feeling of safety”
• Used as a sales technique since Edison
• Used by cities to placate public
• Reducing crime much more complex
• Chicago study showed that increasing lighting
levels can actually increase crime

6. Crime Trend - 1990-2014

7. Lighting Statistics
• 80% is used for Commercial &
Public Exterior Lighting
• ~750 million Outdoor Lighting Fixtures*
Worldwide
• ~160 million Outdoor Lighting Fixtures*
in US
– *Commercial & Public Exterior (Road, Street,
Parking + Buildings)

8. • Total Wasted Energy is approx. 60-70%
overall from:
– Unwarranted (not needed) = 25%
– Over-lighting (excessive illumination) = 25%
– Not dimmed or on curfew = 25%
– Glare =15%
– Uplight = 10%
Lighting Statistics

9. • Approx. Wasted Energy = 1.1 PetaWatt
Hours Annually
– The equivalent output of 500 power plants
– Could power ~ 7,750,000 homes
– Producing 750 million tons of CO2
– Cost = Approximately $110 billion
(US Dollars)
Lighting Statistics

10. • Blue-rich white light increases
perception of glare and…
• Decreases visual acuity/safety
• Increases circadian disruption which..
• Reduces quantity and quality of sleep
• Adversely impacts ecology
AMA Report Warnings

11. • Use warm white light <3000K CCT
– Minimize short wavelength SPD
• Reduce adverse impact from
– Glare
– Light trespass
– Sky Glow
• Minimize circadian disruption
• Reduce ecological impact
AMA Recommendations

12. Lighting Quality & Color
 Use appropriate color temperature
 Assess public preferences
 More blue SPD increases perception of
glare and light trespass
 Use IES BUG Rating UG 0 or 1 fixtures

13. Lighting Quantity & Controls
 Broad Spectrum white light is different
 Increased visibility allows lower levels
 Most neighborhoods w/ speed limits 30 MPH
or less don’t need street lights
 Use pedestrian centric lighting
 Use controls to adapt lighting to time of night
 RP-8-14 includes adaptive control guidance
based on road classification
 Community can choose lower lighting levels

14. Public Outreach
• DOTs need to engage lighting experts for
design and planning
• Pilot test all options: fixtures/CCT/controls
• Solicit public preferences with surveys/tours
• Use professionals to devise “neutral” questions
• Engage broad demographic sampling
• Use social media, web and print advertising,
and mail to engage widest population diversity
• Hold frequent town hall public meetings
• Base final decisions on the data

15. Lighting Standards
• Lighting standards can’t keep pace with rapid
evolution in technology.
• Committees for lighting standards rely on
volunteers and are very slow moving.
• No money available for needed research
• Luminance and uniformity are inferior metrics
• Standards traditionally have erred on the side
of more light

16. Lighting Standards
• We see by contrast, not brightness.
• Broad-spectrum white light improves both
luminance and chrominance contrast
• Standards will likely evolve to reduce
recommended luminance levels for broad-
spectrum white light

17. Legal
• US has 70% of world’s supply of lawyers
• Fear of litigation dictates US lighting policy
• Lighting lawsuits are rare…
• Judgments even more so
• Cities routinely settle out of court

18. • No legal requirement for public lighting
• Adhering to recognized lighting standards
does not always provide liability shield
• Negligence due to poor maintenance is most
common claim
• Cities can establish their own standards
based on research or community preference
Legal

19. Best Practices
• Smart controls maximize savings/flexibility
• Right amount of light for the time of night
• Headlights work better <=30 mph
• Use pedestrian centric lighting
• Reduce glare, uplight, & light trespass
• Preserve neighborhood ambiance with
appropriate luminance & color temperature
• Adopt ecologically responsible choices

20. Thank you
Please join SOLA today
Bob Parks, LC, MIES
Executive Director
Smart Outdoor Lighting Alliance
(bparks@sola.lighting)