BS EN 12665 is the European standard that defines lighting design fundamentals, measurement criteria, and specification requirements.
Released in its latest edition in May 2024, this 82-page standard provides the framework lighting professionals need for compliant, efficient installations. This comprehensive 82-page guide sets the foundational requirements and terms for the entire industry. It gives professionals a common language.
BS EN 12665 is the European standard that defines lighting design fundamentals, measurement criteria, and specification requirements.
Overview of EN 12665 and Its Importance in Lighting
Think of this standard as the foundational rulebook that ensures everyone is speaking the same language on a project. It creates a level playing field for all professionals involved.
EN 12665 establishes the basic terms and criteria for light and lighting across all applications. Whether you’re designing warehouse lighting, retail illumination, or office lighting systems, this standard provides the common language that prevents costly specification errors.
The standard covers essential lighting concepts including luminous flux, illuminance levels, and luminance distribution. For UK lighting designers and consultants, it’s the foundation for meeting building regulations and creating systems that perform long-term.
EN 12665 Key Terms and Definitions Explained
Understanding Basic Lighting Terms
The standard defines critical lighting terminology that professionals use daily:
Light: Radiant energy of wavelengths between 380-780 nanometers that the human eye perceives visually.
Lighting: The deliberate application of light to spaces, objects, or surfaces to enable visual tasks and create appropriate visual environments.
Luminous Flux: The total amount of light emitted by a source, measured in lumens (lm).
Illuminance: The amount of light falling on a surface, measured in lux (lx). This is crucial for specifying task lighting requirements.
Luminance: The brightness of a surface as perceived by the eye, measured in candelas per square meter (cd/m²).
These lighting terms and definitions eliminate confusion between designers, engineers, electrical contractors, and facility managers on projects.
Criteria for Specifying Lighting Requirements Under EN 12665
The Standard's Specification Framework
EN 12665 establishes systematic criteria for specifying lighting that covers:
Illuminance Requirements: Minimum and maintained illuminance levels for different tasks and spaces.
Uniformity: The ratio of minimum to average illuminance across a working area, ensuring consistent light distribution.
Glare Control: Limiting discomfort and disability glare through unified glare rating (UGR) values.
Colour Rendering: Minimum colour rendering index (CRI) values for accurate colour perception.
Colour Temperature: Correlated colour temperature (CCT) specifications for appropriate visual ambiance.
Energy Efficiency: Lighting power density targets that balance visual requirements with energy consumption.
Maintenance Factors: Accounting for light depreciation, luminaire dirt accumulation, and lamp mortality over time.
This systematic approach ensures lighting design projects address all critical performance aspects from day one.Understanding the Standard's Scope
This document defines basic terms and criteria that apply everywhere. Whether you’re lighting a warehouse, a shop, or an office, the same fundamental principles hold true.
Its first job is to establish a common terminology. This eliminates confusion between designers, engineers, and contractors. The second is to create a systematic framework for specifying lighting requirements.
This systematic approach means no critical aspect is forgotten. It’s designed for a wide range of users, from lighting consultants and architects to facility managers and electrical installers.
Key Features and Up-to-Date Relevance
The 2024 edition is particularly valuable. Its 82 pages of guidance include updated definitions reflecting modern LED technology.
The criteria for specifying lighting now address contemporary needs like energy efficiency and human-centric design.
Proper specification from the start supports long-term maintenance and refurbishment. This aligns directly with our goal of eliminating lighting waste through smarter, regenerative design.
Key Terms and Criteria Specified in EN 12665
Miscommunication in lighting specifications can lead to expensive errors, making precise definitions critical for project success. The standard provides the common language that ensures everyone understands exactly what’s required.
EN 12665 Lighting Design Applications
Commercial Lighting Design
For offices, retail, and commercial spaces, the standard guides specifications for:
- Task lighting at workstations and desks
- General ambient lighting levels
- Display and accent lighting requirements
- Emergency and safety lighting integration
Industrial Lighting Applications
Warehouse, manufacturing, and industrial environments require specific considerations:
- High bay and low bay luminaire selection
- Safety lighting for hazardous areas
- Task lighting for inspection and detailed work
- Energy-efficient LED system design
How EN 12665 Supports Sustainable Lighting Projects
The framework enables precise lighting specification that prevents over-lighting and reduces energy waste. By defining exact requirements upfront, designers create systems optimized for:
- LED technology integration
- Daylight harvesting opportunities
- Maintenance and refurbishment rather than replacement
- Reduced carbon footprint and operational costs
This approach aligns with BREEAM, LEED, and other green building certifications.
Implementing EN 12665 in UK Lighting Projects
Meeting UK Building Regulations and Standards
EN 12665 works alongside:
- Building Regulations Part L: Energy efficiency requirements for lighting systems
- BS EN 12464-1: Specific illuminance requirements for workplace lighting
- IET Wiring Regulations (BS 7671): Electrical installation standards for lighting circuits
The standard provides the foundational criteria that support compliance with these regulations.
Practical Benefits for Lighting Professionals
For Lighting Designers and Consultants:
- Clear specification criteria reduce ambiguity in tender documents
- Common terminology improves client communication
- Systematic framework ensures no critical factors are overlooked
For Electrical Contractors and Installers:
- Precise requirements eliminate guesswork during installation
- Standard definitions align with manufacturer specifications
- Verification procedures confirm compliant installations
For Facility Managers:
- Defined maintenance factors support lifecycle planning
- Clear performance criteria enable effective commissioning
- Framework facilitates lighting refurbishment projects
EN 12665 vs Other Lighting Standards
While EN 12665 provides fundamental definitions and criteria, it works with other standards:
EN 12464-1: Specifies actual illuminance values for workplaces (EN 12665 defines the measurement principles)
EN 15193: Addresses energy performance calculations for lighting (uses EN 12665 terminology)
CIE Standards: International Commission on Illumination standards that complement EN requirements
Understanding how EN 12665 fits within the broader standards landscape helps professionals apply it correctly.
Key Takeaways: Using EN 12665 Effectively
The 2024 edition of BS EN 12665 reflects modern LED technology and contemporary lighting design needs including human-centric lighting and circadian considerations.
For successful implementation:
- Master the basic terms and definitions to communicate effectively across project teams
- Apply the systematic criteria framework from initial concept through final verification
- Use the standard to justify design decisions and support building regulation compliance
- Specify maintenance factors that ensure long-term performance, not just initial installation values
Criteria for Specifying Lighting Requirements
The standard establishes clear criteria for specifying lighting requirements. This framework covers task needs, energy efficiency, and maintenance planning.
Using these terms criteria specifying approaches prevents common pitfalls. It ensures installations meet both immediate and long-term performance goals.
Technical Insights into Lighting Design and Measurement
The true power of this framework emerges when we examine how it systematically guides professionals through every stage of lighting requirement setting.
Framework and Aspects Considered
This systematic approach ensures we consider all critical factors when setting requirements. The framework covers everything from initial space assessment through to final verification procedures.
We find the standard’s attention to maintenance factors particularly valuable. These technical considerations determine whether lighting performs adequately throughout its service life rather than just at installation.
The framework also addresses integration with other building systems. This includes heat output from luminaires affecting HVAC loads and control system compatibility.
Following this structured approach reduces the risk of overlooking critical aspects. It ensures emergency lighting, daylight interaction, and surface finishes are properly considered in the specification process.
For refurbishable systems, the framework provides guidance on luminaire accessibility and component serviceability. This supports our mission of enabling long-term maintenance rather than disposal.
Practical Applications and Implementation in the UK
For UK lighting professionals, the practical implementation of this framework transforms abstract principles into daily project successes. We see it as an essential toolkit for navigating both technical and regulatory landscapes.
This approach is vital for creating systems that meet specific requirements for safety and performance. It applies equally to commercial, industrial, and residential lighting applications.
Guidelines for Use in Lighting Design Projects
When specifying lighting for a UK project, the standard’s criteria provide a clear checklist. This is crucial for meeting building regulations and workplace requirements.
We use the framework to address common questions. These include earthing requirements for metal fittings and certification for the UK market.
This systematic process ensures every light and lighting decision is justified. It supports better collaboration between designers, engineers, and contractors.
Benefits for Industry Professionals
The primary benefit is a significant reduction in specification errors. Using the criteria for specifying lighting leads to more accurate tender documents.
This clarity improves communication and project outcomes. It also supports our mission by promoting systems designed for long-term maintenance.
Professionals who master these lighting applications gain a competitive edge. They deliver safer, more efficient light lighting solutions that clients value.
Conclusion
This comprehensive framework transforms lighting specification from subjective guesswork into precise engineering. The document provides the essential basic terms criteria that create a common language across our industry.
Implementing these criteria specifying lighting leads to systems that perform as intended for decades. This systematic approach supports our mission of creating refurbishable light lighting solutions that eliminate waste.
We encourage every professional to adopt this framework in their next project. Staying current with standards ensures your lighting requirements reflect contemporary best practices. This gives you a competitive edge in delivering superior light environments.
FAQ
What is the main purpose of the EN 12665 standard?
The main purpose of EN 12665 is to establish the fundamental criteria for specifying lighting requirements. It provides a clear framework for lighting design by defining basic terms and detailing the essential aspects that must be considered for any lighting application, ensuring consistency and quality across projects.
Who should use this standard in their work?
This standard is essential for a wide range of industry professionals, including lighting consultants, electrical engineers, MEP managers, and facility management companies. It’s particularly valuable for anyone involved in planning, designing, or specifying lighting installations for commercial, industrial, or retail environments.
How does EN 12665 define ‘light’ and ‘lighting’?
The standard provides precise definitions for these core concepts. It defines ‘light’ as the aspect of radiant energy that a human observer can perceive visually. ‘Lighting’ is then defined as the application of light to spaces and objects to make them visible, encompassing the entire system from the light source to the illuminated environment.
What are the key criteria for specifying lighting according to this document?
The standard outlines crucial criteria such as illuminance levels, luminance distribution, and glare restriction. It sets the framework for specifying requirements that ensure visual comfort, performance, and safety, covering aspects like uniformity and colour rendering that are vital for effective lighting design.
Is EN 12665 relevant for sustainable lighting projects?
Absolutely. While its primary focus is on technical specifications, the framework it provides is fundamental for achieving sustainable outcomes. By enabling precise specification of lighting requirements, it helps avoid over-lighting and energy waste, aligning perfectly with goals for efficiency and reducing environmental impact.
How does this standard benefit a lighting design project in the UK?
For UK projects, EN 12665 offers a recognised and authoritative basis for design decisions. It ensures compliance with European norms, provides a common language for project teams, and helps create lighting schemes that are both effective and meet rigorous quality benchmarks, saving time and reducing errors.
