LED Lighting for Tunnels - High-Quality Professional Supplier | MASONLED

Introduction

As the backbone of urban public transportation systems, metro networks carry millions of passengers daily. Lighting is not merely basic infrastructure that provides visual conditions for passengers — it is a critical factor in operational safety, passenger experience, and energy conservation. Unlike general building lighting, metro lighting faces unique challenges: 24/7 operation, enclosed underground spaces, complex electromagnetic environments, frequent vibration and impact, and constrained maintenance conditions.

The maturity of LED technology has brought revolutionary changes to metro lighting. Compared to traditional fluorescent and metal halide luminaires, LEDs offer significant advantages for metro applications: higher efficacy (≥150 lm/W), longer lifespan (≥50,000 hours), instant start, precise optical control, and intelligent control capabilities. However, metro lighting design is far more complex than general indoor lighting — station halls, platforms, tunnels, and equipment areas each have distinct functional requirements, and parameters such as illuminance, CCT, CRI, glare, flicker, and EMC are all interlinked.

This guide is intended for metro owners, design institutes, engineering contractors, facility managers, and lighting suppliers, covering standards frameworks, performance parameters, zonal lighting requirements, luminaire selection, optical design, intelligent controls, installation and maintenance, and quality assurance.

1. Standards and Regulatory Framework

1.1 GB/T 16275-2025 — Urban Rail Transit Lighting

GB/T 16275-2025 is the most fundamental national standard for urban rail transit lighting, released in 2025 as a comprehensive upgrade to the 2008 edition. This standard aims to adapt to new trends such as the widespread adoption of LED technology and the development of intelligent controls, addressing the limitations of the previous version in areas like energy efficiency metrics and light source type coverage.

Standard Evolution Path:

• 1996 Edition: Focused solely on underground railway lighting

• 2008 Edition: Expanded to cover the entire system (metro/light rail)

• 2025 Edition: Added new frontier content including DC power supply and non-visual lighting

Key Technical Changes:

• Added provisions for LED light source selection

• Added luminaire selection requirements for different spaces

• Added adjustable‑height luminaire selection provisions

• Added anti-detachment requirements for luminaires in special spaces

• Added provisions for LED driver selection

• Added glare evaluation limits for tunnel lighting

• Added color deviation requirements for LED lamps and luminaires

• Added limits for flicker and stroboscopic effects

• Revised the general color rendering index requirements for light sources

International Alignment: The revision process referenced international standards including CIE and IEC, achieving technical alignment in glare control, emergency lighting, and other metrics.

Scope: Applicable to lighting design, construction acceptance, and operation and maintenance phases of new construction/renovation projects, specifying lighting technical requirements for all functional areas from station halls and platforms to tunnels.

1.2 GB 50157-2013 — Code for Design of Metro

GB 50157-2013 is the comprehensive design code for metro engineering, with clear provisions for lighting:

• Normal tunnel illuminance: ≥ 5 lx

• Emergency lighting duration: ≥ 60 minutes

• Emergency switching time: ≤ 5 seconds

1.3 GB 50034-2013 — Standard for Lighting Design of Buildings

This standard classifies metro stations as “underground traffic spaces” under the “transportation buildings” category, imposing special requirements on lighting quality and energy efficiency metrics for underground spaces.

1.4 DB44/T 1620-2015 — Design Standard for LED Lighting in Metro Spaces

A Guangdong provincial standard specifically addressing LED lighting design for metro environments. It specifies design requirements for LED lighting in various metro spaces including platforms, tunnels, stations, and train carriages — covering LED luminaire selection, layout, illuminance, CCT, energy efficiency, and maintenance.

1.5 Electromagnetic Compatibility (EMC) Standards

With dense low-voltage equipment in metro tunnels, EMC compliance is a core acceptance requirement. Key standards include:

• GB/T 17743-2021: Limits and methods of measurement of radio disturbance characteristics of electrical lighting and similar equipment

• GB 17625.1-2022: Electromagnetic compatibility limits — limits for harmonic current emissions, with lighting equipment required to meet Class C

• GB 7000.1-2015: Luminaires — General requirements and tests

• GB 17625.2, GB/Z 17625.5, GB/T 17626.8, GB/T 18595: Related EMC standards

Total harmonic distortion of luminaire current shall be ≤ 10%.

1.6 International Standards Reference

• EN 12464-1: Defines workplace lighting requirements including road and tunnel lighting, specifying minimum illuminance levels, uniformity, and glare control

• CIE 88: Guide for the lighting of road tunnels and underpasses

• ANSI C136.31: Minimum vibration performance requirements for roadway lighting luminaires

2. Key Performance Parameters

2.1 Illuminance

Different functional areas of metro systems have varying illuminance requirements. The following table shows recommended illuminance values from key standards:

International Reference Values:

• Station hall/arrival hall: 200–300 lx, uniformity ≥ 0.6

• Platform: 200 lx, uniformity ≥ 0.4

• Ticket vending/ATM areas: 300–500 lx

• Control areas/gates: 200–300 lx

• Technical areas: 150–200 lx

Adjacent area illuminance ratio: Should be controlled within a reasonable range to avoid visual discomfort caused by sudden illuminance changes.

2.2 Correlated Color Temperature (CCT)

Color Consistency Requirements:

• Light source CCT in public areas such as station halls and platforms should remain consistent

• CCT deviation controlled within ±150K

• Color consistency SDCM ≤ 5 (ANSI standard)

2.3 Color Rendering Index (CRI)

2.4 Glare Control (UGR)

Glare Control Strategies:

• Use semi-cutoff distribution to control upward light output ratio and avoid direct glare

• Luminaires with protective covers should control maximum surface luminance

• Tunnel lighting should use dedicated luminaires with low-glare design

2.5 Illuminance Uniformity

2.6 Flicker

Metro lighting shall comply with the flicker requirements in Clause 4.3.5 of the standard. High-frequency LED drivers are recommended to minimize flicker effects. GB/T 16275-2025 has added new limits for flicker and stroboscopic effects.

2.7 Power Factor (PF)

Metro lighting has relatively high power factor requirements:

• Minimum requirement: PF ≥ 0.90

• Recommended: PF ≥ 0.95

2.8 Ingress Protection (IP) Rating

2.9 Vibration and Impact Resistance

Metro tunnels are subject to piston wind effects from trains and continuous low-frequency vibration, requiring luminaires with stable mechanical and electrical performance:

• Vibration resistance: Tunnel luminaires shall comply with ANSI C136.31, withstanding at least 1.5G (standard) or 3.0G (high vibration) cycles

• Impact resistance: IK10 is mandatory to withstand falling debris, maintenance tools, and mechanical impact from passing goods

• Anti-vibration and anti-detachment: Luminaires used in high-vibration areas shall have anti-vibration and anti-detachment measures

• Corrosion resistance: Luminaires in tunnels and depot maintenance areas shall be constructed from corrosion-resistant materials

2.10 Lifetime Requirements

• L70 Lifetime: ≥ 50,000 hours (recommended)

• Accelerated aging test: ≥ 7,000 hours lumen depreciation testing per LM-80

3. Zonal Lighting Requirements

3.1 Station Hall Public Area

The station hall is the primary area for ticketing, security screening, and passenger circulation. Lighting design should focus on:

• Illuminance: 200–300 lx

• CCT: 4000–5000K (5000K recommended)

• CRI: Ra ≥ 80

• UGR: ≤ 22

• Uniformity: ≥ 0.7

Special areas: Ticket vending machine areas should have illuminance elevated to 300 lx.

3.2 Platform Waiting Area

The platform is the core area for passenger waiting and boarding/alighting, with safety as the primary consideration:

• Illuminance: 150 lx (standard), may range 100–200 lx

• Platform edge: Shall achieve ≥ 150 lx to ensure safety

• During train arrival: May be elevated to 200 lx

• CRI: Ra ≥ 80

Platform-track boundary: The platform edge should have a clear illuminance gradient or light strip marking to alert passengers to the safety distance.

3.3 Entry/Exit Passages

Passages connect the ground level to the underground:

• Illuminance: 150 lx

• Emergency lighting: ≥ 50 lx

• Transition lighting: To avoid adaptation issues (passengers ascending from below on escalators), transitional lighting should be installed above escalators and passages at intervals of 1–2 meters

3.4 Equipment Management Areas

Including control rooms, communication rooms, switchgear rooms, etc.:

• Illuminance: 300 lx

• Control rooms: 500 lx

• CRI: Ra ≥ 80

• CCT: 4000–5500K

3.5 Tunnel Lighting

Metro tunnels primarily serve train passage, with maintenance personnel entering only briefly:

• Normal illuminance: ≥ 5 lx

• Uniformity: ≥ 0.7

• Distribution: Semi-cutoff distribution, controlling upward light output ratio

• Emergency lighting: Duration ≥ 60 minutes, switching time ≤ 5 seconds

3.6 Commercial Areas (if applicable)

Commercial areas within metro stations require both high illuminance and visual appeal:

• Illuminance: 500 lx

• CRI: Ra ≥ 80

4. Luminaire Selection

4.1 Basic Selection Principles

1. Environmental adaptability: Select LED luminaires based on the environmental conditions of the lighting space

2. Ingress protection: Areas with dust/water protection requirements (e.g., tunnels) shall use IP65 or higher

3. Vibration resistance: High-vibration areas shall have anti-vibration and anti-detachment measures

4. Safety protection: Areas susceptible to mechanical damage or where light sources may detach shall have protective measures

5. Corrosion resistance: Tunnels and depot maintenance areas shall use corrosion-resistant materials

6. Hazardous areas: Areas with flammable, explosive, or corrosive materials shall comply with relevant national standards

4.2 Main Luminaire Types

4.3 LED Drivers

LED driver selection shall comply with the following requirements:

• Shall use drivers that meet national standards

• Shall satisfy EMC requirements (harmonics ≤ 10%)

• Shall have over-voltage, over-current, and over-temperature protection

• Dimmable drivers (0–10V/DALI) are recommended to support intelligent control

4.4 Special Area Luminaire Requirements

• Lift/lower luminaires: High-ceiling spaces (e.g., depots) shall use lift/lower luminaires for easy maintenance

• Anti-detachment luminaires: Special areas shall have anti-detachment measures

• Tunnel luminaires: Shall use combined luminaire and mounting bracket assemblies; mounting brackets shall be constructed from stainless materials

5. Optical Design and Light Distribution

5.1 Distribution Requirements

Metro lighting shall employ appropriate distribution design:

• Semi-cutoff distribution: Controls upward light output ratio to avoid direct glare

• Tunnel lighting: Shall meet specific distribution type requirements to ensure clear driver visibility

• Carriage lighting: Half-peak edge angle ≤ 60°

5.2 Transition Lighting Design

Metro stations are transition spaces from ground to underground, making illuminance gradient design critical:

• Entry/exit passage illuminance controlled at 100–200 lx

• Transitional lighting installed above escalators and passages at 1–2 meter intervals

• Avoid sudden illuminance changes that cause light/dark adaptation issues

5.3 Unified Glare Rating (UGR) Control

UGR is an important metric for evaluating indoor lighting glare:

• Use CCD imaging luminance meters for spatial glare analysis

• Metro platform UGR ≤ 19, train carriage UGR ≤ 22

• Select appropriate luminaire shielding angles and distribution curves

5.4 Optical Simulation

Metro lighting design should utilize professional optical simulation software (e.g., DIALux) for:

• Illuminance distribution simulation

• Uniformity verification

• Glare assessment

• Emergency lighting effect verification

6. Intelligent Lighting Control Systems

6.1 System Architecture

Metro intelligent lighting control systems typically employ a centralized management, zonal control architecture:

• Central controller: Unified management and scheduling

• Zone controllers: Zonal control by station hall, platform, passage, etc.

• Terminal devices: LED luminaires + dimming drivers + sensors

6.2 Control Protocols

6.3 Control Strategies

Metro intelligent lighting systems can achieve the following control functions:

6.4 Emergency Lighting Control

Emergency lighting systems shall provide:

• Switching time: ≤ 0.5s (EN 60598-2-22)

• Duration: ≥ 90 min

• Dual-power switching reliability: ≥ 5,000 cycles

7. Installation and Maintenance

7.1 Installation Requirements

Tunnel Luminaire Installation:

• Luminaire installation in traffic areas shall satisfy safety requirements under maximum tunnel wind speed of 30 m/s

• Shall use combined luminaire and mounting bracket assemblies; mounting brackets shall use stainless materials

General Installation Requirements:

• Luminaires and lighting control devices shall be nationally certified

• Shall be manufactured from Class B or higher flame-retardant materials

• Photobiological safety shall comply with GB/T 20145

• Outdoor and open areas at depots shall meet wind resistance requirements

Lift/Lower Luminaires: High-ceiling spaces shall use lift/lower luminaires for ground-level maintenance access

7.2 Maintenance Schedule

Recommended metro lighting maintenance:

7.3 Operation and Maintenance Requirements

GB/T 16275-2025 Chapter 12 specifies detailed requirements for operation, maintenance, and measurement, including:

• Periodic illuminance measurement

• Luminaire cleaning and replacement

• Emergency lighting periodic testing

• Intelligent control system function verification

8. Quality Assurance and Testing

8.1 Core Testing Items

Metro LED luminaires shall pass the following tests:

8.2 Key Certification Requirements

8.3 Supplier Quality Evaluation Criteria

When selecting a metro LED lighting supplier, consider:

• Complete EMC test compliance: Each model with corresponding complete test report

• Complete documentation for approval: Meeting project acceptance requirements

• Lead time: Small-scale retrofit projects require short lead times

• Customization capability: Adaptation to project-specific requirements

• Reliability track record: Products that pass complete testing procedures can achieve 62% lower failure rates compared to conventional approaches

Metro LED Lighting Project Checklist

This guide is intended for metro owners, design institutes, engineering contractors, facility managers, and lighting suppliers. For project-specific design recommendations, consult a professional lighting design firm or LED metro lighting manufacturer.