Night Sky Solutions by Unilamp

Advancing Environmentally Responsible Outdoor Lighting

Outdoor lighting today plays a vital role in preserving the natural night environment while delivering visual comfort and enhancing architectural spaces. DarkSky International provides respected global guidance for responsible lighting, and Unilamp proudly supports these principles.

While several Unilamp luminaires are officially certified by DarkSky International, many more of our products already follow DarkSky-aligned performance standards—including controlled uplight, reduced glare, and minimal spill light—even without formal registration.

To clearly communicate this performance and enable more informed, environmentally conscious decisions, Unilamp has introduced Night Sky Solutions, our zoning system based on DarkSky environmental categories E0–E4. This approach provides a clear and positive way to understand environmental suitability across our luminaire portfolio.

What Are Night Sky Solutions?

Night Sky Solutions classify Unilamp luminaires according to their optical performance and BUG rating (Backlight, Uplight, Glare), aligning with DarkSky environmental zones while presenting the information in a clear, user-focused format. And limiting unnecessary spill light. The Night Sky Solution makes these characteristics easier to identify and apply.

Night Sky Solutions Zones (E0–E4) — Practical Application

E0 – Highest Sensitivity / Highest Control

For observatories, dark-sky reserves, astronomical sites, wildlife protection areas, and sacred or heritage locations.
Requires the most stringent control of uplight, glare, and spill light.

E1 – High Sensitivity / Very High Control

For temples, cultural landmarks, heritage zones, and protected natural landscapes.
Demands tightly focused optics and minimal light intrusion.

E2 – Low Brightness / Residential & Suburban

For residential communities, rural areas, gardens, and low-density neighborhoods.
Lighting should be gently directed, comfortable, and respectful of nearby homes.

E3 – Medium Brightness / Urban Mixed-Use & Commercial

For commercial districts, mixed-use urban areas, streets, and parking environments.
Requires balanced illumination with controlled optical distribution.

E4 – High Brightness / City Centers & Landmarks

For active urban environments, city centers, façades, plazas, and architectural highlights.
Allows higher brightness levels and wider optical performance while maintaining responsible light control.

Zone hierarchy:

A luminaire suitable for a stricter zone (e.g., E0 or E1) may be used in any higher-numbered zone. This ensures each lighting solution respects the environmental sensitivity of its application.

The principle is simple:

A luminaire approved for E2 can be used in E3 or E4, but not in stricter environments such as E1 or E0. A product suitable for E0 or E1 can be used anywhere because it meets the highest optical-control requirements.

This hierarchy ensures each fixture respects the environmental sensitivity of its application.

Environmental	Zone Category	ULWR (max%)
E0	Astronomical Observable dark skies, UNESCO starlight reserves, IDA dark sky places	0
E1	Intrinsically dark areas, e.g., “National Parks”, “Areas of Outstanding Natural Beauty” or other “dark landscapes”	0
E2	Low district brightness areas, e.g. Rural or small village locations	2.5
E3	Medium district brightness areas, Small town centres or urban locations	5
E4	High district brightness areas, e.g., Town/city centres with high levels of night-time activity	15

BUG Rating as the Technical Foundation

Night Sky Solutions utilize BUG ratings to confirm optical precision and environmental compatibility.

For example:
• A B1 U1 G1 luminaire demonstrates strong control of backlight, uplight, and glare
• Such performance may qualify it for various Night Sky Solutions zones, depending on project needs
• Sensitive zones such as E0 or strict E1 typically require very tight control, e.g., B0 U0 G0

Higher-number zones allow broader distributions, while lower-number zones require more restrained optics and minimal light escape.

Why Unilamp Uses the E0–E4 Night Sky Solutions System

1. Clear Environmental Alignment

Night Sky Solutions provide a straightforward understanding of how each luminaire aligns with environmental sensitivity, from the most protected landscapes to vibrant city centers.

2. Recognition of Night-Sky-Friendly Performance

Whether officially certified or naturally compliant in performance, Unilamp luminaires that support DarkSky principles are clearly identified within the Night Sky Solutions framework.

3. Commitment to Responsible Lighting

Night Sky Solutions reinforce Unilamp’s dedication to sustainable and respectful lighting practices, guiding the use of each product according to its environmental suitability.

Download Our Night Sky Solution Brochure and Luminaire List

For designers, lighting consultants, and project partners who require detailed technical information, we provide dedicated downloadable resources to support accurate planning and specification.

Night Sky Solution Brochure includes:

• Full lists of Unilamp luminaires that meet Night Sky Solution requirements
• BUG rating references for each model
• Recommended E0–E4 environmental zone applications
• Optical diagrams and key performance notes

To access the complete documentation, please use the links below:

Download the Night Sky Solutions Brochure (PDF)
Download the Luminaire List for Night Sky Solutions (Excel)

Summary

• Night Sky Solutions represent Unilamp’s positive, transparent, and environmentally aligned interpretation of DarkSky principles. They offer:
• Clearly defined E0–E4 environmental zones
• Insight into how luminaires meet or exceed DarkSky expectations
• A structured approach ensuring luminaires are used responsibly and appropriately
• Recognition that while some Unilamp products are formally DarkSky certified, many more naturally fulfill DarkSky lighting criteria

With Night Sky Solutions, Unilamp provides lighting professionals with a confident, environmentally responsible path to selecting the ideal luminaire for every project.

For more information, visit www.unilamp.co.th or contact online@unilamp.co.th