THE AGL ENGINEERING CENTRE by Precision AGL Academy · Apron Lighting

Apron Floodlighting Design Lux Levels, Pole Layout & Foundations

Understand apron illuminance and uniformity criteria, LED floodlight selection, pole layout and mounting height, glare control, photometric calculation, foundations, electrical coordination and maintenance for airport aprons.

Overview

Airport Apron Floodlighting Design

Airport apron floodlighting provides illumination for aircraft parking stands, aircraft servicing, passenger boarding and disembarkation, baggage handling, cargo operations, refuelling and other authorized apron activities.

A well-designed apron lighting system must provide sufficient and reasonably uniform illumination while controlling glare, unwanted shadows, spill light and interference with airport operations.

The design requires more than selecting high-wattage LED floodlights. It involves establishing the required illuminance, evaluating horizontal and vertical lighting performance, selecting suitable luminaires, determining mast locations and heights, completing photometric calculations, coordinating foundations and electrical infrastructure, and verifying the installed system.

Important: The lighting values in this guide are reference criteria, not a substitute for the approved project specification. The applicable airport requirements, current standards, design basis and acceptance criteria must be verified before engineering or installation.

Topics covered

Lux levels & uniformityLED floodlightsPole layout & heightGlare controlPhotometric calculationLux surveyPole foundationsElectrical & controlsMaintenanceDesign checklist
1 · System

What Is an Airport Apron Floodlighting System?

An airport apron floodlighting system illuminates the areas where aircraft are parked, serviced and prepared for departure or arrival.

Unlike runway and taxiway lighting, which uses purpose-designed visual aids to guide aircraft movement, apron floodlighting generally illuminates larger work areas from elevated luminaires mounted on poles, masts or suitable structures.

Main Components of an Apron Lighting System

ComponentFunction
LED floodlightsProvide the required illumination and beam distribution
Lighting poles or mastsPosition luminaires at calculated heights and locations
FoundationsTransfer structural loads safely into the ground
Mounting brackets and aiming arrangementsSupport the luminaires and allow the specified aiming configuration
Electrical distributionSupplies and protects the lighting circuits
Cables and connectionsProvide electrical connections between the distribution equipment and luminaires
Earthing and bondingProvide the specified electrical safety and fault-protection arrangements
Lighting controlsProvide the intended switching, scheduling, dimming or monitoring functions where specified
Photometric design softwareModels illumination, uniformity and relevant lighting performance
Inspection and maintenance recordsSupport condition monitoring and verification throughout the equipment's service life
The complete system should be designed around aircraft stand geometry and operational needs. Floodlight wattage alone cannot establish whether the selected equipment will achieve the required illumination.
2 · Lux & Uniformity

Apron Lighting Lux Levels and Uniformity

Illuminance is the amount of luminous flux incident on a surface per unit area. It is measured in lux (lx).

Apron lighting design should establish the required illuminance for each area, the measurement plane, the uniformity criteria and any additional visual-performance requirements.

2.1 Reference Lux Levels for Aircraft Stands

ICAO's aerodrome design guidance and the corresponding provisions in EASA's published aerodrome certification specifications give the following reference criteria for apron floodlighting. Indian Standard IS 11116:1984 also contains similar apron-lighting criteria. Their application must be checked against the governing project requirements.

Apron area / measurementReference illuminanceUniformity or other criterion
Aircraft stand — horizontal illuminance20 lux averageAverage-to-minimum ratio not greater than 4:1
Aircraft stand — vertical illuminance20 lux at 2 m above the apron in relevant directionsAssess in the directions relevant to the aircraft stand and servicing activity
Other apron areasHorizontal illuminance equal to 50% of the average horizontal illuminance on aircraft standsAverage-to-minimum ratio not greater than 4:1
Service equipment, parking areas and service roads near the apron limit10 lux average horizontal illuminance is specified in IS 11116:1984Verify the applicability of this provision to the project

These are reference criteria, not universal values for every apron activity. Security needs, specialist servicing tasks, project specifications and other operational requirements may require different or additional provisions.

For Indian projects, consult the applicable airport requirements and current standards catalogue. BIS materials list IS 11116:1984, Code of Practice for Lighting for Airport Aprons, with a review entry dated May 2020; confirm its current status and contractual applicability before using it as the design basis.

2.2 Horizontal Illuminance

Horizontal illuminance is measured on a horizontal reference plane, typically the apron surface. It helps assess illumination across aircraft parking positions, service areas and other working surfaces.

The photometric model should identify the calculation grid and the surface area over which the illuminance statistics are evaluated. The grid must represent the actual apron geometry rather than omit poorly illuminated areas.

2.3 Vertical Illuminance

Vertical illuminance is measured on a vertical plane and is important where personnel need to identify aircraft sides, markings, service connections and other relevant features.

For aircraft stands, the cited reference criteria include vertical illuminance at a height of 2 m above the apron in relevant directions. The designer must establish the appropriate measurement directions for the actual stand and intended servicing activities.

Horizontal illuminance alone is therefore not a complete measure of apron lighting performance.

2.4 Illuminance Uniformity

Uniformity describes how consistently light is distributed across the assessment area. A common average-to-minimum ratio is:

U0 = Eavg / Emin

Eavg is the average illuminance. Emin is the minimum illuminance within the defined calculation area. U0 is the average-to-minimum ratio. For the cited aircraft-stand reference criterion, the ratio should not exceed 4:1.

For example, if the average horizontal illuminance is 24 lux and the minimum is 8 lux:

U0 = 24 / 8 = 3.0

The ratio is 3:1. Whether the design is acceptable depends on all applicable criteria, not uniformity alone.

Key point: A high average lux value does not guarantee good lighting. A design may achieve a high average while leaving particular areas too dark or creating excessive brightness in others.

Related Guides

AGL photometry

Why the same light gives a quarter of the lux at twice the distance.

ILLUMINANCE · LIGHT ARRIVING ON A SURFACE E = I ÷ d²E ÷ 4 d2d 4× the area, so a quarter of the illuminance 12345 1SOURCEIntensity I, in candela 2SURFACEReceives the light 3DISTANCE (d)Source to surface 4ILLUMINANCE (E)Flux per area, in lux 5INVERSE SQUAREDouble d, E falls to ¼ SCHEMATIC · SMALL SOURCE, SURFACES FACING IT, NOT A REAL FIXTURE
Figure 1. Illuminance falls with the square of distance, so mounting height and spacing drive the lux on the apron.
AGL Visual Encyclopedia: Illuminance Luminous Flux Light Distribution
3 · Required Lux Level

What Determines the Required Apron Lux Level?

The required lighting level depends on the intended use of the area and the governing project requirements. Consider the following during the design review:

Aircraft stand configuration and the types of aircraft using itPassenger boarding and disembarkation arrangementsBaggage, cargo and ground-service activitiesRefuelling and maintenance tasksAircraft markings, surface markings and obstacle markings that personnel need to identifyApron roads, equipment parking areas and pedestrian routesSecurity and emergency requirementsExisting surrounding lighting and operational constraintsThe governing standard, approved project specification and acceptance method

Different tasks do not necessarily need the same illuminance. A passenger boarding area, an aircraft servicing position and a peripheral service road may have different design criteria.

Avoid selecting a single lux value for the entire apron without first defining the areas and their intended functions.
4 · LED Floodlights

LED Floodlights for Airport Aprons

LED floodlights are widely considered for apron lighting projects because suitable products can provide efficient light output, controlled beam distributions and flexible switching or dimming options where supported by the equipment. However, suitability must be demonstrated against the project's photometric, electrical, environmental and operational requirements.

Key LED Floodlight Selection Parameters

ParameterWhy it matters
Luminous fluxIndicates the total quantity of light emitted
Luminaire efficacyIndicates how efficiently electrical power is converted into luminous output
Photometric distributionDetermines where the light is directed and how it is distributed
IES / LDT photometric fileProvides the luminaire intensity data used in a photometric calculation
Correlated colour temperatureDescribes the apparent colour tone of the white light
Colour rendering propertiesHelp determine how accurately relevant object colours can be identified
Glare performanceSupports evaluation of potentially distracting light at relevant viewing positions
Ingress protectionIdentifies the specified protection against ingress of solids and water
Corrosion resistanceSupports equipment suitability for the site's environmental conditions
Thermal managementInfluences temperature-related performance and equipment life
Driver performanceAffects electrical compatibility, operation, control and maintenance
Surge protectionMust suit the project's electrical protection requirements
Control compatibilityDetermines whether the luminaire supports the specified switching, dimming or monitoring functions
Maintenance accessAffects inspection, cleaning, replacement and servicing requirements
Warranty and supportInfluences the lifecycle cost and availability of replacement equipment

Why Wattage Is Not Enough

Two floodlights with the same rated electrical power can have different luminous output and different beam distributions. One may concentrate more light in a particular direction, while another distributes light over a wider area. The resulting illumination across the apron will therefore differ.

Floodlight selection should use verified photometric data, mounting geometry and calculation results rather than wattage alone.

Colour Identification

Apron lighting should provide light in which the colours used for aircraft markings, routine servicing and relevant surface and obstacle markings can be correctly identified. This requirement appears in the cited aerodrome guidance.

When comparing luminaires, evaluate the documented colour-rendering performance and other relevant characteristics against the project requirements. Do not assume that two luminaires with similar colour temperature will provide identical colour rendering.

5 · Pole Layout

Apron Floodlighting Pole Layout

Pole layout determines the coverage, uniformity, glare characteristics and maintainability of the lighting system. A suitable design must consider the apron geometry, aircraft parking arrangement, surrounding infrastructure and intended maintenance strategy.

5.1 Factors Affecting Pole Location

Design factorKey consideration
Aircraft stand geometryEnsure the required areas are illuminated without creating excessive dark zones
Aircraft dimensions and parking orientationAccount for large aircraft surfaces, stand clearances and potential shadows
Apron dimensionsDetermine the required coverage and feasible mounting positions
Passenger boarding bridgesConsider obstruction, glare and access limitations
Terminal buildingsAvoid unwanted spill light and conflicts with building interfaces
Control tower sight linesAvoid glare and obstructions affecting controllers
Taxiways and aircraft movement areasMinimise distraction and operational interference
Service roads and pedestrian routesProvide the required coverage in designated movement and work areas
Maintenance accessAllow safe access for cleaning, aiming checks and replacement
Existing utilitiesCoordinate pole locations with buried and above-ground services
Obstacle clearance requirementsAssess mast height and location under applicable aerodrome safeguarding criteria
Structural and civil constraintsConfirm the feasibility of foundations, cable routes and installation access
The final layout should be coordinated with the airport's operational and engineering stakeholders before construction.

5.2 Mounting Height

Mounting height affects the illuminated area, beam spread, uniformity, glare and the physical feasibility of the installation.

The ICAO Aerodrome Design Manual, Doc 9157 Part 4, discusses mounting floodlights at sufficient height to reduce direct and indirect glare, including guidance related to the maximum eye height of pilots of aircraft regularly using the airport. The manual also emphasizes the need to consider mast location, height and the operational environment.

This guidance should not be treated as a stand-alone rule for selecting a pole height. Final mounting height must be established through the applicable design process, accounting for photometric performance, obstacle limitations, structural constraints, aircraft clearances and maintainability.

5.3 Lighting from Multiple Directions

Floodlights should be arranged and aimed so that each aircraft stand receives light from two or more directions where required by the applicable design criteria. This helps reduce shadows and improves visibility across aircraft surfaces and the working area.

Where practical, favour a coordinated distribution across the stand and apron over a layout that directs individual intense beams at isolated points.

5.4 Pole Spacing

Pole spacing should be determined from the photometric calculations and actual site geometry. There is no universal spacing that applies to every apron. The result depends on:

Pole height and positionLuminaire optics and mounting orientationLuminous output and photometric distributionApron dimensions and stand arrangementThe presence of buildings, bridges or other obstructionsRequired average and minimum illuminanceRequired uniformityGlare and spill-light constraints
Do not finalise a pole-spacing schedule before validating the proposed locations and aiming through the photometric model.

Floodlight masts between stands, with overlapping coverage and stand guidance.

TERMINAL BUILDINGVDGSAIRCRAFT STANDFLOODLIGHTMASTLEAD-IN LINEAPRON TAXILANE◄ TO TAXIWAYTO TAXIWAY ►PLAN VIEW · ILLUSTRATIVE, NOT TO SCALE
Figure 2. Masts sit between stands so that each stand is lit from more than one direction and no mast blocks the aircraft or guidance.
AGL Visual Encyclopedia: Apron Lighting Layout Aircraft Stand Lighting Interface VDGS Interface with Stand and Apron Systems
Floodlights illuminating an air force flightline at night
Photo 1. High-mast floodlights lighting a flightline at night. Mast position, aiming and spacing decide how evenly the parked aircraft are lit.Credit: USAF photo by Senior Airman Steven Cardo, 2024. Released public domain (US Government work). Original source
6 · Glare Control

Glare Control and Light Spill

Glare can interfere with the visibility of pilots, air traffic controllers, apron controllers and ground personnel. Unwanted light can also affect surrounding areas and create visual distraction.

Glare control should therefore be treated as a design requirement, not as an adjustment to be addressed only after installation.

ICAO apron floodlighting guidance calls for adequate illumination with minimum glare and recommends restricting direct light toward the control tower and landing aircraft. It also highlights suitable aiming and the control of light above the horizontal plane.

Glare-Control Measures

Select luminaires with suitable photometric distributions.
Locate poles to avoid direct glare toward relevant viewing positions.
Aim luminaires in accordance with the approved calculations and installation requirements.
Consider shielding or optical accessories where supported and specified.
Review glare toward the control tower and aircraft approaching or taxiing near the apron.
Consider glare at personnel eye level and along service routes.
Evaluate light spill onto nearby buildings, roads and operational areas.
Recheck the design if a luminaire model, pole height or aiming angle changes.
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The assessment should use the actual luminaire photometric files and site geometry. A visual check alone may not identify all glare or spill-light concerns.

Glare and spill are controlled by where the beam points, not by lux alone.

GLARE AND SPILL · WHERE THE BEAM POINTS DECIDES WHO IS DAZZLED1 · TILTED UP OR UNSHIELDEDAPRON SURFACEEYE LEVEL = HORIZONTALLight above horizontal reaches cockpits and the tower2 · AIMED DOWN AND SHIELDEDAPRON SURFACEEYE LEVEL = HORIZONTALBeam stays below horizontal and falls on the standsSCHEMATIC · SIDE VIEW · AIMING AND SHIELDING MUST BE VERIFIED ON SITE AFTER INSTALLATION
Figure 3. Aiming below horizontal and shielding keep light off cockpits, the tower and neighbouring areas.
AGL Visual Encyclopedia: Edge-Light Beam Light Distribution
7 · Photometric Calculation

Apron Floodlighting Photometric Calculation

A photometric calculation estimates how light from the proposed luminaires will be distributed over the selected areas. The calculation should use verified luminaire photometric data and the proposed installation geometry. It should represent the relevant obstructions, calculation surfaces and acceptance criteria.

7.1 Required Design Inputs

Before starting the calculation, collect:

Apron geometry

Overall dimensions, aircraft stand boundaries, stand centre lines, service areas and adjacent movement areas.

Pole layout

Proposed coordinates, mounting heights, bracket details and luminaire orientation.

Luminaire data

Manufacturer, model, rated power, verified luminous output and IES/LDT photometric file.

Aiming parameters

Luminaire tilt, rotation and other orientation details required by the modelling software.

Obstructions

Terminal buildings, passenger boarding bridges, hangars, other structures and relevant site features.

Calculation criteria

Required horizontal and vertical illuminance, uniformity and any project-specific glare or spill-light criteria.

Surface assumptions

The specified calculation plane and any reflectance or environmental assumptions needed for the study.

7.2 Photometric Calculation Workflow

01

Step 1: Define the calculation area.

Separate aircraft stands, service areas, apron roads and other relevant zones.

02

Step 2: Establish the grid.

Select appropriate grid spacing and measurement planes in accordance with the applicable calculation method and project requirements.

03

Step 3: Import photometric data.

Use the correct data for the exact luminaire model and optical configuration proposed.

04

Step 4: Place the luminaires.

Enter actual or proposed pole locations, heights and mounting orientations.

05

Step 5: Set the aiming angles.

Use the planned installation configuration and evaluate glare-sensitive directions.

06

Step 6: Run the calculations.

Determine average, minimum and relevant maximum illuminance, uniformity and the other required outputs.

07

Step 7: Review isolux plots and results.

Identify dark areas, excessive concentrations, uneven coverage and potential spill-light concerns.

08

Step 8: Refine the layout.

Adjust pole positions, mounting height, optics or aiming when justified, then recalculate.

09

Step 9: Verify the design basis.

Confirm that the results meet the specified criteria and that the model corresponds to the proposed installation.

10

Step 10: Issue the design records.

Retain the calculation report, luminaire data, layout, assumptions and revision information.

7.3 What Should a Photometric Report Include?

A professional apron floodlighting calculation report should generally identify:

Project name, location and design revisionDesign scope and calculation areasApplicable standards and project criteriaSoftware and calculation-method information, where requiredManufacturer, luminaire model and photometric data referencePole coordinates and mounting heightsLuminaire aiming informationHorizontal illuminance resultsVertical illuminance results where requiredAverage, minimum and uniformity resultsRelevant calculation grids and isolux plotsGlare and spill-light assessments where specifiedDesign assumptions and limitationsDeviations, outstanding items and reviewer approvals
The report should be traceable to the exact layout and equipment configuration being proposed.

Related Guides

AGL photometry

Nested isocandela contours show where a luminaire sends its light.

ISOCANDELA DIAGRAM (SCHEMATIC) SAME FIXTURE, DIFFERENT OBSERVERS PEAK 50% 10% HORIZONTAL ANGLE LEFT RIGHT VERTICAL ANGLE UP DOWN EACH CONTOUR JOINS DIRECTIONS OF EQUAL INTENSITY A ON AXIS: FULL INTENSITY B NEAR EDGE: REDUCED C OUTSIDE BEAM: LOW FIXTURE INTENSITY RECEIVED DEPENDS ON ANGLE FROM THE AXIS
Figure 4. The photometric file describes the luminaire distribution that the lux calculation is built on.
AGL Visual Encyclopedia: Light Distribution Isocandela Diagram Measurement Points
8 · Calculation vs Survey

Lighting Calculation Versus On-Site Lux Measurement

A photometric calculation is a prediction based on the model inputs and assumptions. An on-site illuminance survey measures the installed system under the conditions at the time of the survey. Both can be important for design verification and acceptance.

Comparison of Calculation and Measurement

AspectPhotometric calculationOn-site lux survey
PurposePredict performance before installation or modificationMeasure actual illuminance after installation or during assessment
Main inputsPhotometric files, layout, mounting geometry and calculation criteriaInstalled lighting, measuring points, operating conditions and measurement method
Common outputPredicted average, minimum and uniformity values, plus plotsRecorded illuminance measurements and calculated statistics
Main limitationResults depend on input-data accuracy and model assumptionsResults depend on the actual installation and survey method
Typical useDesign development and comparison of layout alternativesVerification, acceptance assessment and maintenance investigations

On-Site Survey Considerations

Use a suitable illuminance meter with calibration or verification status as required.
Identify the exact survey area and measurement plane.
Use the approved grid or measurement-point layout.
Record the luminaire operating condition and any required control settings.
Follow the specified procedure for ambient light and other environmental conditions.
Record all readings and units.
Calculate average, minimum and uniformity using the defined assessment area.
Compare results with the applicable project acceptance criteria.
Document equipment changes, aiming changes or other installation differences.
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For accurate comparison, the calculation and survey should use compatible areas, measurement planes and acceptance definitions.

A single lux reading at one point is not sufficient to demonstrate that an entire apron meets its illumination and uniformity requirements.

A calculation predicts, a survey confirms, and the gap between them needs an explanation.

CALCULATION VS SURVEY · SAME GRID, TWO SOURCES, ONE COMPARISONCALCULATED · PREDICTED LUXMEASURED · INSTALLED LUXLuminaire photometric file, geometry,maintenance factor, obstructionsCalibrated meter, defined grid points,conditions at the time of surveyCOMPARE · EXPLAIN ANY GAPLuminaire output and ageingMounting height and aimingDirt and lamp or LED conditionSurface reflectance and obstructionsMeter position, height and conditionsSCHEMATIC · GRID SHADING IS ILLUSTRATIVE · NO MEASURED VALUES SHOWN
Figure 5. Calculated and measured grids are compared point by point on the same calculation plane.
AGL Visual Encyclopedia: Light-Intensity Measurement Measurement Points
9 · Foundations

Apron Lighting Pole Foundations and Structural Coordination

Floodlighting poles and masts are structural installations. Their foundations should be designed by appropriately qualified personnel using the actual site data and applicable structural requirements. The foundation design cannot be finalized solely from the pole height or luminaire wattage.

Main Foundation Design Inputs

InputWhy it matters
Pole or mast dataEstablishes the geometry, mass and manufacturer-specified support requirements
Luminaire arrangementInfluences the wind-exposed area and applied loads
Wind design conditionsDetermines relevant structural loading under applicable requirements
Soil investigationProvides information about bearing, settlement and other geotechnical conditions
Foundation geometryDetermines how loads are transferred into the ground
Anchor bolts and base plateMust match the approved structural and manufacturer details
Corrosion and environmentInfluences material selection and durability provisions
Underground servicesAffects foundation position and excavation planning
Cable entries and ductsRequires coordination with the structural and electrical drawings
Drainage and surface levelsHelps prevent unsuitable water accumulation around the foundation
Maintenance accessSupports inspection, replacement and servicing arrangements
Airport safeguardingEnsures the pole location and height meet applicable aerodrome requirements

Pole Foundation Coordination Checklist

Confirm the approved pole location and height.
Obtain the manufacturer's pole and base details.
Confirm structural design loads and relevant project requirements.
Review available geotechnical information.
Coordinate the foundation with underground utilities.
Confirm the anchor-bolt and base-plate arrangement.
Coordinate cable ducts, earthing and bonding requirements.
Review drainage and finished surface levels.
Verify access for installation and future maintenance.
Obtain the required structural and project approvals before construction.
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Do not use a generic foundation size for every pole. The foundation must be suitable for the actual structure, loading, soil and site conditions.

Foundation block, anchor bolts and the conduit rising to the equipment.

SIDE SECTION · A FOUNDATION FOR ELEVATED EQUIPMENT GROUND LEVEL CABLE IN CONDUIT EQUIPMENT ABOVE GROUND FRANGIBLE COUPLING ANCHOR BOLTS (TEMPLATE-SET) REINFORCED CONCRETE BLOCK COMPACTED SUB-BASE CONDUIT RISES THROUGH BASE WHERE CIVIL MEETS AGL 1 POSITION & LEVEL Set from the lighting layout 2 ANCHOR BOLTS Template-set position and height 3 ORIENTATION Equipment faces the correct way 4 CONDUIT ENTRY Cable rises through the base 5 LOADS & SUB-BASE Sized for wind, mass, soil
Figure 6. The pole foundation, anchor bolts and cable entry are designed together with the pole and luminaire loads.
AGL Visual Encyclopedia: Foundations Fixture Foundations
10 · Electrical & Controls

Electrical Distribution, Protection and Controls

The electrical infrastructure should support the intended lighting arrangement and allow safe operation, inspection and maintenance.

Electrical Design Considerations

Confirm the connected load and required circuit arrangementSelect cables based on the specified electrical and installation requirementsCalculate voltage drop and other relevant electrical parametersSpecify suitable distribution and protection equipmentCoordinate earthing and bonding with the overall electrical designConsider surge protection where required by the designProvide suitable isolation and maintenance arrangementsProtect cable routes and connections against relevant environmental and mechanical risksCoordinate switching, control and monitoring functions where specifiedProvide identification, circuit schedules and controlled drawings

The final design should be prepared and reviewed under the applicable electrical and airport engineering procedures.

Lighting Control Strategy

Depending on the project, controls may provide:

Local switchingCentralized controlTime-based switching schedulesApproved dimming or lighting scenesEnergy monitoringFault reporting or status indicationIntegration with an existing airport monitoring system

The control strategy should be based on the intended operation and the selected equipment's verified capabilities.

Do not assume that every LED floodlight supports continuous dimming or integration with every control platform. Confirm compatibility before specifying the system.
11 · Emergency Lighting

Emergency and Operational Lighting Considerations

Apron lighting supports night-time work and passenger activities. The design should consider the implications of an electrical supply failure or loss of a lighting circuit. The requirement for emergency or contingency illumination depends on the airport's operational requirements, safety assessment and project specification.

Where additional provision is required, evaluate:

The areas where illumination must remain availableThe expected function and required coverageThe specified duration and power sourceSeparation or resilience requirements where applicableControl and changeover arrangementsInspection, testing and maintenanceThe required records and acceptance criteria
Emergency lighting requirements must be defined from the governing documents. Do not assume that every apron has the same emergency illumination requirement or that normal floodlighting automatically provides a compliant emergency arrangement.

What takes over when normal control or supply is lost, and how recovery is verified.

EMERGENCY CONTROL · KEEPING LIGHTING SAFE WHEN NORMAL CONTROL FAILS 1NORMALALCMS CONTROLAND MAINS POWER 2LOSSCONTROL, POWER ORAN EMERGENCY 3FALLBACKBACKUP TAKES OVERUNDER PROCEDURE 4RECOVERRESTORE, THENVERIFY STATUS LOSING THE SCREEN IS NOT LOSING THE LIGHTS — THE CCRS KEEP DRIVING THEM BACKUP CONTROL ANOTHER POSITION OR LOCAL AT THE CCR SECONDARY POWER GENERATOR OR BATTERY TAKES OVER THE LOAD PRESET SETTINGS AGREED LIGHTING FOR AN EMERGENCY EMERGENCY OFF REMOVE ENERGY FROM A HAZARD KEY POINT A FALLBACK ONLY WORKS IF IT IS TESTED — AND RECOVERY ENDS WITH VERIFIED STATUS SCHEMATIC · NOT TO SCALE
Figure 7. Fallback provisions are chosen in advance, with recovery confirmed before normal operation resumes.
AGL Visual Encyclopedia: Emergency Control Standby power and UPS
Mobile floodlight units stowed on an air force flightline
Photo 2. Mobile floodlight units kept ready on a flightline. Temporary lighting like this is one operational fallback when fixed apron lighting is unavailable.Credit: USAF photo by Airman 1st Class Tiffany Del Oso, 2022. Released public domain (US Government work). Original source
12 · Maintenance

Apron Floodlighting Maintenance

A properly designed system still requires inspection and maintenance to preserve its intended performance. Maintenance planning should cover luminaires, poles, foundations, electrical equipment, controls and the condition of relevant installation records.

Routine Maintenance Checklist

Inspect luminaires for visible damage or deterioration.
Check optical surfaces for contamination and clean them according to the manufacturer's instructions.
Review reported lighting outages and recurring defects.
Inspect accessible mounting arrangements and fasteners as required by the maintenance procedure.
Check poles, brackets and foundations for relevant signs of deterioration.
Review cable entries, enclosures and connections as required.
Check the control functions and status indications specified for the equipment.
Confirm that replacement luminaires match the approved specification.
Verify aiming after replacement or adjustment where required.
Perform illuminance measurements when required by the maintenance or acceptance procedure.
Record defects, corrective action and required follow-up.
Update maintenance and equipment records.
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Inspection intervals should be established through the applicable maintenance programme, manufacturer recommendations, environmental conditions and observed equipment performance.

When Is a Lux Survey Needed?

A lux survey may be appropriate during initial acceptance, following significant alterations, after relevant aiming changes, when persistent dark areas are reported or when required by the inspection programme.

The survey should follow the specified measurement method and use the applicable acceptance criteria. Results should be traceable to the equipment condition and assessment area at the time of measurement.

From requirement list to plan, safe work, verification and records.

HOW REQUIREMENTS TRAVEL INTO MAINTENANCE 1 REQUIREMENT LIST Standards, manufacturer data, regulator rules and contract terms OUTPUT: MAINTENANCE ITEMS 2 MAINTENANCE PLAN Tasks, intervals, spares, tools and acceptable condition OUTPUT: WORK INSTRUCTIONS 3 PREPARE SAFELY Permit, isolation, earthing, tower coordination and spares OUTPUT: SAFE TO WORK 4 CARRY OUT WORK Preventive tasks and corrective repairs OUTPUT: WORK DONE 5 VERIFY Post-work tests and checks against the acceptable condition OUTPUT: FIT FOR SERVICE 6 RECORD & REVIEW Records signed, circuit restored, findings reviewed against intervals OUTPUT: MAINTENANCE RECORDS FEEDBACK LOOP Findings, failures and repeat faults go back to the plan, so tasks, intervals and spares are reviewed against real results. PLAN FIRST · THEN ISOLATE, WORK, VERIFY, RESTORE AND RECORD SIMPLIFIED SEQUENCE · FOLLOW YOUR SITE PERMIT AND ISOLATION PROCEDURE
Figure 8. Maintenance is a loop: plan, prepare safely, carry out, verify and record, then review.
AGL Visual Encyclopedia: Maintenance Requirement Flow Corrective Maintenance Sequence Fixture Alignment (Maintenance)
13 · Common Mistakes

Common Mistakes in Apron Floodlighting Design

Selecting luminaires by wattage alone

Why it matters

  • Wattage does not establish the resulting illumination, uniformity or glare performance.

Designing only for horizontal illuminance

Why it matters

  • Some apron activities and reference criteria require assessment of vertical illuminance as well.

Checking average lux without uniformity

Why it matters

  • An acceptable average can conceal poorly illuminated areas.

Using unverified photometric files

Why it matters

  • The calculation should represent the exact luminaire model and optical configuration proposed.

Placing poles before reviewing site constraints

Why it matters

  • Buildings, aircraft stands, service routes, utilities and control tower sight lines may affect suitable locations.

Ignoring glare

Why it matters

  • Excessive direct light toward pilots, controllers or personnel can undermine the usability of the lighting system.

Directing each floodlight at individual aircraft

Why it matters

  • The overall distribution should be assessed so the stand receives balanced illumination from appropriate directions.

Using a generic pole height or spacing

Why it matters

  • Both depend on the layout, photometric performance, constraints and structural design.

Ignoring foundations and cable coordination

Why it matters

  • Foundation conflicts or inadequate access can lead to redesign and installation delays.

Replacing a luminaire without checking its photometric data

Why it matters

  • An alternative fixture may produce a different distribution and change the calculated or measured performance.

Treating a calculation as proof of installed performance

Why it matters

  • Where required, the installation must be verified using the specified inspection and measurement methods.
14 · Design Checklist

Apron Floodlighting Design Checklist

Use this checklist as an initial design-review aid.

Design Basis

Confirm the governing standards and project specification.
Define the apron areas and their intended activities.
Establish the horizontal and vertical illuminance requirements.
Confirm uniformity criteria and measurement planes.
Identify relevant glare, spill-light and colour-rendering requirements.
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Equipment and Photometry

Select luminaires based on verified photometric data.
Confirm the exact model and optical distribution.
Prepare the proposed pole layout.
Enter mounting heights and aiming details.
Model relevant buildings, bridges and obstructions.
Calculate horizontal and vertical illuminance where required.
Check average, minimum and uniformity results.
Review glare and spill-light performance where specified.
Record assumptions and calculation limitations.
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Civil and Electrical Coordination

Confirm pole locations against the approved site layout.
Coordinate foundations and relevant structural loads.
Check underground services and cable routes.
Confirm electrical distribution and protection.
Coordinate earthing, bonding and control functions.
Review maintenance access and replacement arrangements.
Obtain required technical approvals.
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Installation and Acceptance

Verify equipment and pole locations against approved drawings.
Confirm luminaire mounting and aiming.
Inspect relevant civil and electrical installation records.
Complete the prescribed functional checks.
Perform lux measurements where specified.
Review compliance with the approved criteria.
Document defects and corrective actions.
Issue the required as-built drawings and test records.
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FAQ

Frequently Asked Questions

Q1What lux level is required for airport apron lighting?

A commonly cited reference criterion for an aircraft stand is an average horizontal illuminance of 20 lux, a uniformity ratio not greater than 4:1, and vertical illuminance of 20 lux at 2 m above the apron in relevant directions. Other apron areas may use different criteria. Confirm the applicable standard, airport requirements and project specification before using these values for design.

Q2What is the uniformity ratio for apron floodlighting?

The cited aircraft-stand criterion uses an average-to-minimum illuminance ratio not greater than 4:1. The applicable project criteria determine how the area and measurement grid must be assessed.

Q3Are LED floodlights suitable for airport apron lighting?

They can be suitable when the selected luminaires meet the required photometric, electrical, environmental and operational criteria. Selection should be based on verified photometric data and the completed design calculation, not wattage alone.

Q4How is apron floodlighting pole height determined?

Pole height is determined through the photometric design and the relevant structural, operational and aerodrome constraints. The calculation should assess coverage, uniformity, glare and relevant obstructions; structural design must also account for the actual site and loading conditions.

Q5Why should apron floodlights illuminate aircraft stands from more than one direction?

Lighting from different directions can reduce shadows and improve visibility across aircraft surfaces and service areas. The cited apron floodlighting guidance specifically emphasizes this principle.

Q6What is the difference between horizontal and vertical illuminance?

Horizontal illuminance is measured on a horizontal plane, such as the apron surface. Vertical illuminance is measured on a vertical plane and helps assess illumination of vertical surfaces, such as aircraft sides, in the relevant directions.

Q7Which software is used for apron floodlighting calculations?

Photometric software can model luminaires, pole positions, aiming angles, obstructions and calculation grids. Use software that supports the required calculation method and verified photometric data; the software name alone does not establish design compliance.

Q8Is a lux meter survey necessary after installation?

The need for a survey depends on the approved acceptance procedure, project specification and maintenance requirements. Where measurements are required, follow the prescribed grid and method and compare results with the defined acceptance criteria.

Q9How often should apron floodlights be maintained?

The maintenance interval should follow the airport's approved maintenance programme, manufacturer recommendations, environmental conditions and observed performance. Inspection frequency should not be assumed to be identical for every installation.

Q10What is an apron lighting system?

An apron lighting system is the floodlighting installed on the aircraft apron so ground handling, loading, fuelling and servicing can take place safely at night. It normally comprises floodlights, poles or mounting structures, power distribution, control and protection, and it is separate from the airfield ground lighting on runways and taxiways.

Q11What is an apron lighting pole layout?

An apron lighting pole layout is the arrangement of floodlight poles around or on the apron. Pole position, height and spacing are chosen from the lighting calculation to reach the required illuminance and uniformity while controlling glare and spill. It must also respect obstacle limitation and aircraft clearance.

Q12Why use apron lighting LED floodlights?

Apron lighting LED floodlights offer high efficacy, good control of the light distribution, long service life and instant switching. They suit apron use when selected with the right optics and glare control. The luminaire choice should follow the approved design and lighting calculation.

Q13What does apron lighting maintenance involve?

Apron lighting maintenance includes inspecting lamps or LED modules, cleaning optics, checking pole and fixing condition, testing protection and earthing, verifying aiming and measuring illuminance on site. Work at height and work on live equipment follow the airport's permit and safety procedures.

Q14What are airport apron electrical systems?

Airport apron electrical systems are the supply, distribution, protection, earthing and control arrangements serving apron lighting and related equipment. They include feeder circuits, distribution boards, cables, switching or control, and any emergency or backup supply that the project requires.

Q15How does apron lighting energy efficiency improve?

Apron lighting energy efficiency improves with efficient LED luminaires, good optics that put light only where it is needed, suitable control such as dimming or schedules, and correct maintenance. Efficiency must not reduce the required illuminance, uniformity or glare limits.

Q16What is an apron lighting photometric calculation?

An apron lighting photometric calculation predicts illuminance and uniformity on the apron from the luminaire data, mounting height, aiming and layout. It is checked against the required levels, and on-site lux measurements confirm the installed result.

Q17What are the airport apron lighting requirements?

Airport apron lighting requirements are set by ICAO and national requirements and by the airport's own specification. They address illuminance levels, uniformity, glare control and light spill. Confirm the applicable values and the stand types with the airport operator and the approved design.

Related Resources

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Final Note

A reliable apron floodlighting system requires a complete engineering approach that integrates lux levels, uniformity, glare control, luminaire selection, pole layout, foundation design, electrical distribution, photometric calculations and maintenance.

Use the applicable standards and approved project criteria to establish the design requirements. Validate the proposed layout using verified photometric data, coordinate the civil and electrical works, and complete the required verification after installation.

This page provides general educational guidance. Final design, installation, structural approval, testing and acceptance must follow the applicable airport requirements, approved project documents and authorized engineering procedures.

Technical References

  1. ICAO Aerodrome Design Manual, Doc 9157, Part 4 — Visual Aids — guidance on apron illuminance, uniformity, glare control and floodlight arrangement.
  2. EASA Easy Access Rules for Aerodromes — March 2026 revision — apron floodlighting criteria in CS ADR-DSN.M.750.
  3. Indian Standard IS 11116:1984 — Code of Practice for Lighting for Airport Aprons — Indian apron-lighting design, performance and glare-control guidance. Verify current status and applicability before using it as the governing requirement.

The cited ICAO and EASA materials explain the technical basis for the reference values above. The project specification and applicable airport requirements determine which criteria govern a particular installation.

Field Insight

Engineering & Expert Notes

Calculated Lux Is Not Measured Lux
Verification

Verify design values on site with calibrated instruments, using the same grid assumed in the design.

Glare Control Protects Pilots and Ground Crew
Glare

Check aiming, shielding and mounting height. Glare can compromise safety even when average lux is correct.

Uniformity Matters as Much as Average
Uniformity

Dark patches hide hazards. Review the ratio of minimum to average as well as the mean.

Pole Foundations Need Engineering
Structures

Consider wind loads, soil conditions and access for maintenance equipment.

Plan Electrical Protection and Distribution
Electrical

Include discrimination, earthing and surge protection in the design package.

Design for Maintenance Access
Maintenance

Consider how luminaires will be replaced and cleaned without disrupting apron operations.

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