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How this applies to an existing Portfolio Lighting installation

This ANSI/IES RP-43-25: A Plain-English Guide to Outdoor Pedestrian Lighting resource can help when inspecting, repairing or extending Portfolio outdoor lighting. First identify the transformer, its supply connection, the existing cable and the fixture locations; requirements depend on the equipment listing, installation conditions and locally adopted rules.

Portfolio owner’s first step: For Portfolio equipment, compare the actual nameplate and installation instructions with the safety topic below before altering the system.

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Quick Answer: What Is ANSI/IES RP-43-25?

ANSI/IES RP-43-25 is the Illuminating Engineering Society's 2025 Recommended Practice for Lighting Design for Outdoor Pedestrian Applications.

IES describes its purpose as providing pedestrian-oriented illumination recommendations for reassurance, safety, comfort, amenity and enjoyment in outdoor environments within lighting zones LZ-1 through LZ-4.

The intended audience includes lighting practitioners, architects, engineers and the general public.

The key idea: RP-43-25 is about the complete nighttime experience of a pedestrian. It is not simply a table of minimum light levels.

What Changed in ANSI/IES RP-43-25?

The 2025 edition replaces RP-43-22 and expands the standard into a more comprehensive exterior-lighting resource. IES says the updated edition incorporates content from earlier IES material on quality lighting and environmental outdoor lighting.

Updated

Lighting Zones

Refined zone definitions help match the expected nighttime luminous environment to the actual setting.

Expanded

Color

Color is explicitly included because nighttime visual quality cannot be described by illuminance alone.

Expanded

Controls

Controls are part of the outdoor-lighting design discussion rather than an afterthought.

Expanded

Glare Metrics

The current edition includes new glare content and a dedicated glare annex.

The published standard is 103 pages and includes main chapters plus annexes on illuminance recommendations, lighting-zone background, glare and temporal light modulation.

Lighting Zones LZ-1 Through LZ-4: Why They Matter

IES emphasizes that not all nighttime environments are the same. A quiet rural path, suburban commercial walkway and busy urban plaza should not automatically be designed to the same luminous character.

LZ-1Very low ambient-light context

LZ-2Low ambient-light context

LZ-3Moderately high ambient-light context

LZ-4High ambient-light context

Do not choose a lighting zone just because you want more light. The zone is supposed to describe the environment and expected nighttime context.

IES has continued educating designers and reviewers about the revised lighting-zone framework because it influences design decisions, light levels and responsible use of light at night.

Apply this requirement to an existing Portfolio installation

For ANSI/IES RP-43-25: A Plain-English Guide to Outdoor Pedestrian Lighting, use the page’s specific product or problem as the starting point rather than a generic Portfolio Lighting rule. Preserve the exact model or item number when available, document the failed component or symptom, and record the dimensions, ratings, mounting details, and connections that control the repair decision. That evidence makes it possible to distinguish identification, diagnosis, parts matching, and complete replacement instead of treating them as the same task. Continue with Portfolio Parts once the problem has been narrowed.

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RP-43-25 Starts With What Pedestrians Need to See

Outdoor pedestrians need more than enough light to see the pavement directly in front of them. Good pedestrian lighting can support orientation, wayfinding, recognition of other people, detection of terrain changes, comfort, reassurance and transitions between different brightness environments.

Practical test: if the pavement measures well but people cannot comfortably see faces, signs, steps or the path ahead, the lighting problem is not solved.

Glare Is a Core RP-43-25 Issue

The 2025 edition adds updated glare content and includes a dedicated annex on glare in outdoor applications. More lumens can actually reduce useful visibility when a bright source sits directly in the viewer's field of view.

Better

Controlled Source

The person sees the path, people and surrounding objects without staring into a bright LED source.

Worse

Bright Source in the Eye

Measured illuminance can increase while contrast and visual comfort get worse.

For fixture-distribution terminology, see the Outdoor Lighting ANSI Standards Guide.

Environmental Considerations Are Built Into RP-43-25

The IES Outdoor Nighttime Environment Committee addresses pedestrian vision and glare along with nighttime environmental factors such as sky glow and wildlife preservation. RP-43-25 is therefore not simply about making outdoor spaces brighter.

Controls Are Part of the Lighting Design

The 2025 edition explicitly includes controls among its updated content. The correct light level at 8:00 p.m. may not be the correct level at 3:00 a.m.

Design principle: light should respond to actual nighttime need.

Color and Spectrum Matter More Than a CCT Number

The 2025 edition adds explicit color content. Color temperature is useful shorthand, but CCT alone does not fully describe a source's spectrum or how objects and people appear under it.

For outdoor pedestrian spaces, the useful question is not simply “2700K or 3000K?” It is whether the source supports the visual task, fits the nighttime setting and avoids unnecessary environmental impact.

Temporal Light Modulation: Why Flicker Appears in the Standard

RP-43-25 includes an annex on temporal light modulation, commonly called flicker. Modern LED systems can vary output rapidly because of driver or control behavior even when the variation is not obvious to every observer.

Its inclusion is another example of RP-43 moving beyond a simple “how many foot-candles?” approach to outdoor lighting quality.

Inspect the Portfolio power source and outdoor cable route

For ANSI/IES RP-43-25: A Plain-English Guide to Outdoor Pedestrian Lighting, use the page’s specific product or problem as the starting point rather than a generic Portfolio Lighting rule. Preserve the exact model or item number when available, document the failed component or symptom, and record the dimensions, ratings, mounting details, and connections that control the repair decision. That evidence makes it possible to distinguish identification, diagnosis, parts matching, and complete replacement instead of treating them as the same task. Continue with Portfolio Parts once the problem has been narrowed.

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RP-43-25 vs Electrical Code

RP-43 tells you how to think about quality and performance of outdoor pedestrian lighting. It does not tell you everything required to install the electrical system safely.

RP-43-25

Lighting Performance

Pedestrian vision, glare, environment, lighting zones, controls and design.

NEC / Local Code

Electrical Installation

Wiring methods, GFCI, grounding, burial, branch circuits and wet-location installation.

For installation rules, use the Landscape Lighting Electrical Code & Safety Guide.

RP-43-25 and ASHRAE 90.1 can affect the same exterior project, but they serve different purposes. RP-43 helps designers address pedestrian visibility, glare, lighting zones, and nighttime lighting quality, while Standard 90.1 controls energy use through exterior lighting power limits and automatic controls. Our ASHRAE 90.1 exterior lighting requirements guide explains how the energy-code side works and why a project may need to satisfy both standards rather than choosing one or the other.

RP-43-25 vs ADA Accessibility

RP-43 can help with pedestrian visibility, comfort and nighttime usability. ADA standards address physical accessibility such as accessible routes, ramps, parking, entrances, slopes and clearances.

A compliant accessible route can still have poor lighting, and a beautifully lit route can still be physically inaccessible. Strong site design handles both. See the School Campus Lighting Accessibility Guide and Parking Lot Lighting ADA Guide.

A Practical RP-43-25 Design Workflow

  1. Define nighttime use. Who is there, when, and what do they need to see?
  2. Identify the lighting zone.
  3. Map pedestrian tasks. Routes, entrances, faces, signs, hazards and destinations.
  4. Choose the minimum useful light.
  5. Control glare.
  6. Review environmental effects.
  7. Add controls.
  8. Check bright-to-dark transitions.
  9. Verify quantitative criteria in the official standard.
  10. Coordinate electrical compliance.

Common RP-43-25 Mistakes

Using the highest lighting zone to justify more light

The zone should describe the context, not be selected to support a desired fixture output.

Treating horizontal illuminance as the entire design

Pedestrian vision includes faces, objects, signs, terrain, adaptation and glare.

Ignoring glare because the photometric average looks good

A bright source can make the environment harder to see even when a meter reports adequate illuminance.

Running fixtures at full output all night

Controls are part of the current design framework.

Using RP-43 for roads without checking RP-8

Roadways and parking facilities are handled separately.

What This Guide Does Not Reproduce

ANSI/IES RP-43-25 is a copyrighted professional standard sold by the Illuminating Engineering Society. This page explains its scope, structure and design concepts in plain language, but it does not reproduce the standard's detailed illuminance tables, formulas, figures or copyrighted text.

For formal design or specification work, obtain the current standard directly from IES.

ANSI/IES RP-43-25 Chapter Map

↔ Swipe horizontally to see the complete map.

SectionTopicPractical Question 1Introduction and ScopeIs this standard appropriate for the project? 2Pedestrian ConsiderationsWhat does the person using this space need to see? 3Visual ConsiderationsHow do contrast, adaptation and glare affect performance? 4Environmental ConsiderationsHow can unnecessary nighttime impact be limited? 5Five Principles for Responsible Outdoor LightingIs the light useful, targeted and appropriately controlled? 6Community PlanningHow should lighting fit the broader nighttime character? 7Lighting ZonesWhat luminous environment is appropriate? 8Outdoor Lighting Design ProcessHow should the project be worked through? Annex AIlluminance RecommendationsWhat quantitative recommendations apply? Annex BLighting Zone SummaryHow do zone definitions relate? Annex CGlareHow should glare be understood outdoors? Annex DTemporal Light ModulationWhat role can flicker/modulation play?

Repair Portfolio fixtures without assuming every part is interchangeable

For ANSI/IES RP-43-25: A Plain-English Guide to Outdoor Pedestrian Lighting, use the page’s specific product or problem as the starting point rather than a generic Portfolio Lighting rule. Preserve the exact model or item number when available, document the failed component or symptom, and record the dimensions, ratings, mounting details, and connections that control the repair decision. That evidence makes it possible to distinguish identification, diagnosis, parts matching, and complete replacement instead of treating them as the same task. Continue with Portfolio Parts once the problem has been narrowed.

Portfolio replacement parts Portfolio outdoor lighting Portfolio model lookup

RP-43-25 vs RP-47-23 vs RP-8-25

↔ Swipe horizontally to compare standards.

StandardPrimary ApplicationGood Fit ForNot the Main Standard For ANSI/IES RP-43-25Outdoor pedestrian applicationsWalkways, plazas, building approaches, pedestrian-oriented exterior spacesRoadway design ANSI/IES RP-47-23Landscape lightingLandscape elements, gardens, plantings and landscape-lighting techniquesRoadway photometrics ANSI/IES RP-8-25Roadway and parking facilitiesRoads, intersections, parking lots, garages and vehicle-focused facilitiesGeneral landscape aesthetics

A large site can use more than one standard. A campus may use RP-8 for parking areas, RP-43 for pedestrian paths and RP-47 for landscape-lighting features.

Official Sources Used for This Guide

Related Outdoor Lighting Standards & Compliance Guides

ANSI/IES RP-43-25 FAQ

What does RP-43-25 stand for?

ANSI/IES RP-43-25 is Recommended Practice: Lighting Design for Outdoor Pedestrian Applications, published by the Illuminating Engineering Society in 2025.

What happened to RP-43-22?

RP-43-25 is the updated edition; IES identifies RP-43-22 as the previous edition.

What lighting zones does RP-43-25 use?

The standard uses LZ-1 through LZ-4 and includes refined definitions intended to better describe expected nighttime luminous environments.

Does RP-43-25 provide foot-candle recommendations?

IES identifies Annex A as containing illuminance recommendations. This page does not reproduce the copyrighted tables; obtain the official standard for exact project values.

Does RP-43-25 include glare?

Yes. The 2025 edition includes updated glare content and a dedicated annex discussing glare in outdoor applications.

Does RP-43-25 address flicker?

Yes. Annex D covers temporal light modulation, commonly referred to as flicker.

Is RP-43-25 for parking lots?

Pedestrian areas can overlap with parking sites, but roadway and parking-facility lighting is addressed more directly by ANSI/IES RP-8-25.

Is RP-43-25 legally required?

That depends on whether it has been incorporated into a law, ordinance, code, project specification, contract or other enforceable requirement.

Bottom Line

ANSI/IES RP-43-25 is best understood as a framework for designing outdoor places for people, not merely for light meters. Start with the pedestrian task and nighttime context, choose the correct lighting zone, control glare, consider environmental effects, use controls intelligently, and then verify the standard's quantitative recommendations. Pair RP-43 with the appropriate electrical code, product requirements and application-specific standards.

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