Outdoor Lighting Flashcards

Which IES light trespass standard defines the maximum allowable vertical illuminance at a neighboring property line?

Answer: IES G-1-03

IES G-1-03 (Guideline for Security Lighting) and its successor documents specify maximum vertical illuminance limits at property lines to control light trespass.

A coastal boardwalk project must protect sea turtle nesting habitat. Which lamp color is most appropriate for fixtures near the beach?

Answer: Amber (590nm peak)

Amber light peaking around 590nm has minimal impact on sea turtle navigation instincts, which are most disrupted by short-wavelength (blue/white) light.

What is the primary purpose of a photometric cutoff classification (Full Cutoff, Cutoff, Semi-Cutoff) in outdoor luminaires?

Answer: To control the distribution of light above the horizontal plane

Cutoff classifications describe how much light a luminaire emits above the horizontal (90°), directly controlling sky glow and glare contributions.

In outdoor sports lighting design, the term 'uniformity ratio' most commonly refers to which measurement?

Answer: Average to minimum illuminance (Eavg/Emin)

Sports lighting uniformity is expressed as average-to-minimum (Eavg/Emin), with IES RP-6 specifying maximum allowable ratios for various sports and competition levels.

A pedestrian pathway luminaire is specified at 4m mounting height. Light levels comply but glare complaints arise. Which modification best addresses glare without replacing fixtures?

Answer: Install a house-side shield to block light toward pedestrians

House-side shields block direct view of the lamp source from pedestrians' line of sight, reducing disability glare without altering the overall photometric distribution significantly.

Which photometric test method is used to characterize near-field data required for accurate roadway lighting simulations?

Answer: Goniophotometry (far-field IES file)

Standard goniophotometry produces far-field IES photometric files used in roadway and area lighting simulations; near-field data is a specialized format required only for complex optical modeling.

An outdoor plaza uses 3000K LED downlights recessed into a canopy. What CCT would best complement these for accent uplighting on adjacent trees?

Answer: 3000K–3500K to maintain visual coherence

Matching or closely harmonizing CCT across a scene maintains visual coherence; a 3000K–3500K uplight complements the 3000K downlights without jarring color contrast.