Sports Lighting Standards: A Practical Guide to ANSI/IES RP-6-24

ANSI/IES RP-6-24 is the authoritative standard for sports lighting in North America. Published by the Illuminating Engineering Society and approved as an American National Standard, RP-6-24 defines illuminance levels, uniformity ratios, glare limits, and color requirements for virtually every outdoor and indoor sport at every competitive level — from neighborhood recreational fields to broadcast-grade professional stadiums.

Understanding RP-6 is not optional for anyone specifying or designing sports lighting. It’s the document that resolves disputes between contractors, forms the technical basis for permits and approvals, and protects designers from liability when a facility operator claims the lighting isn’t adequate. This guide covers the current RP-6 framework in practical, applicable terms.

What ANSI/IES RP-6-24 Is

RP-6 (Recommended Practice for Sports and Recreational Area Lighting) is one of several application-specific Recommended Practices published by the IES. The most recent edition is RP-6-24, released in 2024, which superseded RP-6-20. Designers should always verify they’re referencing the current edition, as illuminance values and uniformity requirements have been updated between revisions.

RP-6 is a recommended practice, not a mandatory code. However, it achieves effective mandatory status through several mechanisms:

• Many state and municipal codes reference RP-6 directly or adopt its requirements by incorporation
• Most sports governing bodies (FIFA, USSF, USA Football, NCAA, etc.) reference RP-6 illuminance classes in their facility standards
• Broadcast networks (ESPN, regional sports networks) specify minimum illuminance classes in their venue agreements
• Most experienced facility owners require RP-6 compliance documentation as a condition of project acceptance

The Class System: Matching Illuminance to Level of Play

RP-6 organizes sports lighting requirements into illuminance classes (historically labeled Class I through Class V in earlier editions, with Class I being the highest performance level). The current RP-6-24 framework uses a similar tiered approach that aligns with level-of-play:

• Class I / Level I: Professional and major collegiate competitive play with television broadcast. Highest illuminance requirements.
• Class II / Level II: College/university competitive play, minor league professional, and amateur competition with or without television broadcast.
• Class III / Level III: High school varsity and junior varsity competition; adult amateur leagues.
• Class IV / Level IV: Recreational and community leagues, practice facilities, non-competitive use.

Each class specifies both horizontal illuminance on the playing surface and (critically for television) vertical illuminance on planes facing the primary camera positions.

Sport-by-Sport Illuminance Requirements

The following table summarizes horizontal maintained illuminance (Eh) targets from RP-6. These values represent the average maintained illuminance over the primary playing area at end of maintenance cycle.

Football (American)

Class	Avg Horizontal (fc)	Min Horizontal (fc)	Avg Vertical (fc)
Class I (Broadcast Professional)	100	70	75
Class II (High-Level Amateur/College)	75	50	50
Class III (High School/Adult League)	50	30	—
Class IV (Recreational/Practice)	30	20	—

Soccer

Class	Avg Horizontal (fc)	Min Horizontal (fc)	Avg Vertical (fc)
Class I	100	70	75
Class II	75	50	50
Class III	50	30	—
Class IV	30	20	—

Baseball / Softball

Baseball requires attention to multiple zones — the infield, the outfield, and the warning track each carry different requirements. Infields typically require higher illuminance than outfields due to the faster ball speeds and smaller targets involved.

Class	Infield Avg (fc)	Outfield Avg (fc)	Infield Min (fc)	Outfield Min (fc)
Class I	150	100	100	70
Class II	100	75	70	50
Class III	70	50	50	30
Class IV	50	30	30	20

Tennis

Tennis courts are among the most demanding applications for uniformity due to the fast-moving, small target (the ball) and the need for consistent visibility across the full court surface.

Class	Avg Horizontal (fc)	Min Horizontal (fc)
Class I	100	70
Class II	75	50
Class III	50	30
Class IV	30	20

Basketball (Outdoor) and Volleyball

Class	Avg Horizontal (fc)	Min Horizontal (fc)
Class II	75	50
Class III	50	30
Class IV	30	20

Horizontal vs. Vertical Illuminance

This distinction is where many sports lighting specifications fall short, and where broadcast facilities most often fail inspection.

Horizontal illuminance (Eh) is measured on a horizontal plane at field level — it represents how well-lit the playing surface is for athletes and spectators. This is the value most people think of when they think of “how bright is the field.”

Vertical illuminance (Ev) is measured on a vertical plane facing a defined camera or spectator direction — it represents how well a moving player or ball is illuminated against the background as seen from the side. For television, the cameras are positioned at fixed locations, so RP-6 specifies vertical illuminance on vertical planes facing the primary camera positions (typically the press box side of the field).

For broadcast-quality facilities, vertical illuminance is often the more demanding constraint. A football field might achieve 100 fc horizontal relatively easily, but sustaining 75 fc vertical across the entire field — including in zones far from the main pole line — requires more poles, more fixtures, or different aiming strategies than horizontal illuminance alone would demand (consistent with ANSI/IES RP-6-24 Class I targets).

The relationship between horizontal and vertical illuminance depends on the fixture mounting height, aiming angle, and distribution. High-mast designs (80–120 ft poles) with steeply aimed fixtures deliver excellent horizontal illuminance but can produce poor vertical illuminance. Lower, more steeply angled fixtures aimed to maximize vertical illuminance can compromise horizontal uniformity on the sidelines. Sports lighting design is fundamentally the art of balancing these competing requirements.

Uniformity Ratios

RP-6 specifies maximum allowable uniformity ratios for each class. Uniformity ratio is typically expressed as the ratio of maximum to minimum illuminance (Emax/Emin) or average to minimum (Eavg/Emin). Lower ratios mean more even light distribution.

For most sports applications:

Class	Eavg/Emin (Horizontal)	Emax/Emin (Horizontal)
Class I	≤ 2.0:1	≤ 3.0:1
Class II	≤ 2.5:1	≤ 4.0:1
Class III	≤ 3.0:1	≤ 5.0:1
Class IV	≤ 4.0:1	≤ 6.0:1

For broadcast applications, vertical illuminance uniformity is evaluated on the same grid used for horizontal calculations, but the requirement is typically more stringent for Class I: Eavg/Emin of ≤ 2.0:1 on the vertical planes facing cameras.

Poor uniformity creates visible “hot spots” and dark zones that affect athlete performance (a batter losing a pitch in a dark zone), viewer experience (inconsistent video exposure requiring constant camera iris adjustments), and safety (athletes misjudging distances in areas of high contrast).

Glare Control Requirements

RP-6 addresses glare through two mechanisms: spectator/athlete disability glare (the loss of visual acuity caused by high-luminance sources in the field of view) and broadcast glare (veiling illuminance on camera lenses from fixtures in the camera’s field of view).

Glare control measures required or recommended by RP-6 include:

• Luminaire shielding: Fixtures must be fully shielded (cutoff geometry) or equipped with back shields to limit spill light and high-angle luminous intensity.
• Mounting height: Taller poles generally reduce glare angles for both athletes and spectators by moving fixtures above the critical glare zone (above 45°–50° from horizontal for a person standing on the field).
• Fixture aiming: RP-6 recommends limiting the maximum luminous intensity of any fixture directed above the horizontal plane at the camera positions for broadcast facilities.
• Maximum luminous intensity limits: Broadcast facilities may specify maximum allowable luminous intensity (in candela) at specific angles relative to camera sightlines.

Color Requirements for Broadcast

RP-6-24 provides explicit color quality requirements for broadcast-grade installations:

• Correlated Color Temperature (CCT): 5700K is the near-universal standard for broadcast sports lighting. The 5700K CCT provides a “daylight” appearance on camera that matches natural daylight and requires less post-processing correction.
• Color Rendering Index (CRI): Class I broadcast requires CRI ≥ 80, with Ra ≥ 90 strongly preferred by major broadcast networks. R9 (saturated red) ≥ 50 is required for accurate rendering of red uniforms, warning track dirt, and skin tones.
• CCT Consistency: All fixtures on a broadcast field should be specified from the same product family and production lot to minimize fixture-to-fixture CCT variation (Δuv < 0.003 within a lot is achievable with quality LED products binned to ANSI C78.377-2017 tolerances).

Color consistency between fixtures matters on camera in a way that’s imperceptible to the naked eye. A field illuminated with fixtures that vary from 5600K to 5900K appears uniform to spectators but produces visible color banding on broadcast video, especially in slow-motion replays.

Light Trespass and Dark Sky Ordinances

Many sports lighting projects trigger local light trespass and dark sky ordinance reviews, particularly for:

• Facilities near residential neighborhoods
• Sites in jurisdictions that have adopted International Dark-Sky Association (IDA) model lighting ordinances (IDA/IES Model Lighting Ordinance, MLO-2011)
• Projects near airports or protected natural areas

RP-6 requires that photometric studies include a light trespass analysis showing illuminance at property lines, typically requiring ≤ 0.1 fc at residential property lines and ≤ 0.5 fc at commercial property lines (guidance per IDA/IES Model Lighting Ordinance, 2011; specific values vary by ordinance).

LED sports lighting systems should be specified with:

• Full optical cutoff or back shields on fixtures with significant rear-spill distribution
• Dimming and programmable controls allowing the system to power down to 20–30% after scheduled events
• Programmable curfew controls that comply with local ordinance requirements for maximum operational hours

RP-6 acknowledges the tension between achieving adequate uniformity (which often requires fixtures with broader distributions) and minimizing spill. This is a design engineering problem, not a specification problem — and it’s one of the areas where pole placement strategy has the greatest impact.

Working with Designers to Meet RP-6 Compliance

RP-6 compliance is a photometric study deliverable, not just a specification notation. The design process for a compliant sports lighting installation typically includes:

1. Establish the illuminance class: Based on the level of competition, broadcast requirements, and owner’s program. This is a project decision, not an engineering default.
2. Develop initial photometric layout: Determine pole count, heights, locations, and fixture types to meet illuminance and uniformity targets. This is iterative.
3. Produce a full photometric study: Using IES files from the specified fixtures, calculate Eh and Ev grids, uniformity ratios, and light trespass. Compare against RP-6 requirements.
4. Document compliance: Produce a tabular compliance matrix showing each RP-6 requirement alongside the calculated value. This becomes the permit and acceptance document.
5. Post-installation verification: RP-6 specifies measurement protocols using a calibrated photometer on a defined measurement grid. Measured values should match calculated values within ±10% for a quality installation.

The Illumination Pros tools support this entire workflow — from initial feasibility studies through permit-ready photometric documentation — using IES data from all major sports lighting manufacturers.