Lighting Terms and Definitions

Helping You Choose the Best Lighting Solution

Commercial and architectural lighting is a spectacular combination of design, science, and innovative technology.

Using photometry, the science of measuring light in terms of perceived brightness, manufacturers can precisely explain how specific commercial or architectural lighting will perform.

Anyone purchasing commercial lighting or architectural fixtures must understand some extremely important terms and definitions, and be able to decipher specific diagrams.


Reading Photometrics and Specs in LED Lighting

Ambient Lighting – Lighting throughout an area that provides general illuminations.

Ballast – A device used with an electric-discharge lamp to obtain the necessary circuit conditions (wave form, voltage and current) for starting and operating.

Batwing Distribution – A symmetrical light distribution producing light angles to the right and left of the observer with comparatively little direct downward illumination as in the shape of a bat wing.

Beam Spread – 50% maximum candlepower.

Candela (cd) –  This is the term used to compare Luminous intensity. Candela is the unit of measure indicating the luminous intensity (candlepower) of a light source in a specific direction.

Candelas/meter² (cd/m²) – The quality of light that leaves a surface. This is measurement is what the eye can perceive which will offer more information about the quality and comfort of a design rather than its illuminance alone.

Center Beam Candle Power (CBCP) – CBCP is the maximum candlepower a lamp can achieve at nadir (angle between the vertical axis).

Color Temperature (Chromaticity) – The degree of warmth or coolness of a light source measured in degrees Kelvin (K).  The higher the degree K, the more blue, or cooler the lamp appears.  The lower the degree K, the more red or warmer the lamp appears.

Cutoff – Angle between the vertical axis (nadir) and the line of sight when the brightness of the source or its reflected image is no longer visible.

DLC – The DesignLights Consortium (DLC) promotes quality and energy efficient lighting for the commercial sector. When you buy a product that’s on DLC’s Qualified Products List (QPL), you’ve got yourself a superior lighting product.

Efficiency – The comparison between how much light is emitted from a luminaire. Efficiency% = Luminaire Lumens/Lamp Lumens

Footcandles (fv) – The measure of the quality of light that arrives on a surface. Luminaire intensity, direction of the surface, the distance from the luminaire to the surface, and the angle of incidence of the arriving light are all factors that affect illuminance. Undetectable to the human eye, this information is commonly included and used in specifying designs.

Lamp Information – Term used to identify the lamp designation and its initial lumen output.

Lumens (lm) – Luminous flux is measured in lumens (lm) which is the total amount of light produced by a source without taking direction into consideration.

Luminaire Spacing – Luminaire Spacing = SC x Height to Illuminated Plane

Luminance – Indicator of the brightness of an aperture. Spec sheets will sometimes include various viewing directions, the 0 direction being the direction where the light is aimed. Luminance is a primary indicator of the quality and comfort of a lighting system.

Spacing Criterion (SC) – A mathematical calculation of the maximum spacing allowed in order to achieve reasonably even illumination.

Test Number – Used to identify the specific lamp and luminaire combination being tested.

Unit LPW – Indicator of the total system efficiency.

LPW – Lamp Lumens x Luminaire Efficiency/Luminaire Watts

When looking over any manufacturer’s spec sheets, charts and graphics will play a vital role in describing fixture properties. From Candela diagrams to Downlight and Accent Charts, find explanations of each in this list.
The example spec sheet for the Lumenera V2 will give a better idea of how all these terms and diagrams come into play.

Accent – This graphic shows patterns of light from adjustable accent luminaires dependent on lamp type, wattage, lamp tilt and location of illuminated plane.

Beam Aiming – Diagrams allowing a designer to easily choose the right distance from a wall to locate a luminaire and find the center beam of the lamp where desired

Candelas – Diagrams that will graphically illustrate the light intensity at specific directions from nadir..

Cone of Light – Used for rapid lighting comparisons and calculations – cone of light is used to calculate initial footcandle levels for a single unit based on point calculation techniques.

Downlight – These charts show single-unit performance without considering inter-reflections from surfaces.

Wall Wash Data – There are two different kind of Wall Wash Data charts.

  1. Single-unique performance chart that plots the illuminance levels at one-foot increments along and down a wall.
  2. Multiple unit performance charts show the performance of the middle units computed from a four unit layout.


Outfitting a building with lighting is a crucial step in upgrading any industrial facility or architectural project. Understanding the terminology that goes along with choosing fixtures is essential.

Keeping this handy resource close by will make any purchasers life just a little bit easier.

At RLE Industries you will find a wide range of lighting fixtures for nearly any commercial or architectural lighting application imaginable. Click here to start browsing the variety of products or, call a trusted and experienced lighting professional at (888) 318-0500 for any additional questions about upgrading commercial or architectural lighting fixtures.


What Does DLC Approved Mean? Why Does DLC Certification Matter?

The DesignLight Consortium®

Energy Efficiency and Performance Standards

Searching for commercial lighting solutions can be challenging. Industry terms, certifications, and countless fixture options can make upgrading the lighting in any facility feel like a chore. A common term people might run across is “DLC Approved”. Understanding this common certification can pay off in a big way.

Lighting in an industrial facility, shopping mall, outdoor venue or parking lot is absolutely instrumental to improving productivity and safety. Without proper illumination, work won’t get done and safety could be compromised. If any owner of a commercial space is thinking about upgrading lighting, pushing the task off might not be an option. Many buyers are  left scratching their heads when it comes to navigating all the terms that come along with securing commercial lighting, and the explanations below could be exactly what they need to know.

What Is DLC Certification?

DLC certification is handled by The DesignLights Consortium® (DLC), a non-profit organization dedicated to accelerating the widespread use of high-performing commercial lighting solutions. The DLC established product quality specifications to promote high-quality, energy-efficient lighting solutions. They work with utilities and energy efficacy program members, manufacturers, lighting designers, and federal, state, and local entities.

The goal of the organization and certification is to create better energy efficiency programs by helping to identify and verify the highest-performing products and systems.

This voluntary certification initiative is set aside for LED technology and requires these lighting products to comply with specific standards in three areas:

  • Distribution
  • Color
  • Longevity

Only an accredited laboratory can test DLC lighting requirements, and these test results must be submitted directly to the DLC, by the manufacturer.

Rebate Programs with DLC Certification

All across the United States there are utilities that base rebate programs on DLC standards. DLC certified products include high bays, wall packs, lab lamps, roadway luminaires, retrofit-kits, decorative LEDs, and LED panels. Rebates depend on the location of the installation and can vary from place to place. Consulting with qualified professionals like those at RLE Industries is a perfect way to make sure any business is getting the most out of upgrading their lighting fixtures.

Businesses can benefit greatly by adding DLC Approved lighting solutions in a number of different ways. They can save energy, cut electricity costs, and take part in these rebates. Without knowing what to look for, choosing the best lighting options for any unique application will be a monumental challenge. Having a clear understanding of DLC certification, what it means, and why it matters can help purchasers make an informed decision.

If you have any questions about DLC Approved Lighting Options, or would like more info about RLE Industries’ Services, give us a call at 888-318-0500.

Benefits of LED Lighting for Commercial and Architectural Applications

Architects and business owners have a lot to keep in mind when illuminating their buildings, manufacturing spaces or warehouses.

Advancements in LED industrial lighting offer decision-makers more cost-effective options allowing architect’s limitless creative freedom.

The benefits of LED lighting continue to add up.

Design, function, energy and cost savings are all improved when compared to conventional metal halide or fluorescent fixtures.

Cost Savings

In today’s world, businesses and commercial spaces are constantly searching for new ways to reduce costs and save their business money. LED fixtures, both for commercial applications and architectural lighting designs, have enormous cost savings potential. Reducing energy usage, waste, and maintenance costs all add up to a more efficient technology and better-looking bottom line. LED fixtures for commercial and architectural applications have a variety of benefits beyond cost savings, but any business looking to reduce costs should consider updating their lighting fixtures with modern LED options.

Energy Efficiency – The Green Option

It becomes incredibly clear why commercial and architectural lighting has made the move to embrace LED fixtures when looking at the energy being consumed by outdated technologies. Incandescent lights use 10% of the energy they consume to create visible light, the rest is wasted in the form of heat. Halogen fixtures end up wasting 80% of the energy they consume in the form of heat and only 20% of that energy is actually used to create visible light. LED’s on the other hand turn 80% of the energy consumed into visible light and only 20% is wasted in the form of heat.

LED’s are by far the most efficient technology. Furthermore, LEDs can be recycled unlike incandescent bulbs. Using highly efficient LED lighting fixtures for commercial and architectural lighting applications can have a profound impact on the carbon footprint of warehouses, commercial spaces, and large buildings of any kind.

Service Life

LED lights can last up to 25 times longer than incandescent and halogen. This technology even outshines CFLs, with the average LED lasting three times longer than their mercury gas filled counterparts. With an expected operating time of up to 50,000 hours, that means that even if LED lights are in operation for eight hours a day, seven days a week, these lights would last around 10 years before burning out. The impressive resilience of LED technology makes them a perfect option for lighting fixtures in hard to reach areas as well as any commercial or architectural application.

Limitless Design Options

Architectural lighting focuses both on function and design. Fixtures must be visually appealing while also delivering the desired illumination. The versatility of LED technology allows them to be incorporated into sleek fixtures like the Lumenera line. Powerful lighting solutions paired with an elegant design make LED technology the perfect option for architectural lighting solutions.

LED technology has come so far over the past few years. Costs have fallen and more business owners are taking the steps to outfit their facilities with LED fixtures. Businesses in search of cost effective, energy efficient, versatile lighting solutions finally have the ability to achieve each one of these goals by utilizing a single technology. Commercial and architectural lighting is experiencing an incredible transformation, pushed forward through highly efficient and reliable LED technology.

For more information on upgrading the lighting in any commercial space or including LED lighting into an architectural project, call an RLE Industries lighting professional today at 888-318-0500.

HygenX HiClean LED High Bay

HiClean Plus LED High Bay is specifically designed for food processing environments, including: poultry and meat processing, food processing, cold storage, food service and other areas requiring certification to NSF standards. It has a safe optic lens that meets the 'No-Glass' requirement for food areas.

HiClean Plus is made of high grade aluminum with non-exposed stainless steel screws. Its sleek design allows for easy cleaning and ensures no recesses for bacteria to grow in. Designed for the unique needs of food processing environments, you can specify HiClean Plus with confidence.



Item No. HB06-100 HB06-120 HB06-150 HB06-200
Optical Data
System Efficacy 140lm/W
Luminous Flux 14,000lm 16,800lm 21,000lm 28,000lm
Wattage 100W 120W 150W 200W
CCT 3000K, 4000K, 5000K
CRI Ra70, Ra80
Electrical Data
Input Voltage 100-240Vac / 100-277Vac
Input Surge Protection 2kV line-line, 4kV line-earth
Power Frequency 50/60Hz
Power Factor >0.93 >0.93 >0.92 >0.92
Ingress Protection IP65
LED Life Span >50000Hrs(Ta=30°C@L70)
Storage Temperature -40°C to +70°C(-40°F to +158°F)
Operating Temperature -30°C to +50°C(-22°F to +122°F)
Operating Humidity 15-90%RH
Housing Aluminum Alloy
Protection Class Class I
Weight / Packaging
Luminaire Net Weight 7.2±0.3kg
Outlook Dimensions φ489×200mm
Export Carton Size 560×260×565mm




Line Excel LED Strip Light

The Line Excel Strip Light takes advantage of spacing and design. It merges LED perfectly into any office, retail shop, school, hospital, and many other open spaces.

High efficiency and low glare. With a combination of small SMD LEDs and a diffusing lens cover, Line Excel produces a clean, crisp light.

Line Excel is designed to fit directly into your existing grid.



Line Excel Edge

Lumenera V2

The V2 is our most popular light fixture in the Lumenera lighting family, providing a sleek, slim profile design ideal for today’s linear LED lighting in modern offices, hospitality and retail environments.

The narrow profile meets the requirements for wall mounting fixtures outlined by the Americans with Disabilities Act (ADA) and provides smooth accents for illuminating the vertical plane.

For pendants and surface mounting, the V2 is a powerful direct/indirect light source, making this an ideal choice for common areas.

Continuous rows are custom-designed by our engineering team to eliminate light breaks in runs, as well as shadowing.

Powered by Philips LED boards in multiple color temperatures, and with drivers dimmable down to just 1%, the V2 is a practical design for illuminating common areas.


Office Buildings, Schools, Hospitality, Healthcare and Retail Locations


Solid extruded aluminum housing and steel end plates, powder coated matte white finish. Custom colors are available.


  • Philips Xilanium Universal LED Drivers, compatible with 0-10V dimming systems, deliver reliable, smooth dimming performance down to a minimum of 1%.
  • Drivers can be calibrated for specific lumen output.
  • Standard (ST) Philips Fortimo LED boards (83 CRI – Consult RLE for higher CRI) are max 7.5W per foot and High Output (HO) LED boards are max 15W per foot
  • Minimum operation temperature is -25 C. Maximum operating temperature is 50 C


  • Direct optic utilizes a lift and tilt white opal high transmission spread lens for smooth, even illumination
  • Indirect optic utilizes a thin opal spread lens for high transmission and smooth illumination
  • Optional asymmetrical beam reflector for a even spread


  • For pendants, white rounded power cable is an SJ 18/3 conductor wire to canopy mounted to ceiling J-Box.
  • For surface mount, 4″ square plate powder coated lo match finish.
  • For wall mounting, heavy-gauge rolled steel channel painted to match housing is secured to unit which attaches to a galvanized steel wall channel, for ease of installation.


For continuous runs, factory will provide two 1″ steel pins at the end of each module which are inserted in the end grooves of the extrusion. These pins are then inserted into the joining module and are secured at the roof of the housing by a 16 Gauge joiner bracket that goes over the two quarter twenty studs (one stud at the end of each joining module). Each module in the run is labeled for easy field installation.


  • Drivers and LED boards are rated for 50,000 hours; 5 Year Warranty
  • ARRA Compliant
  • UL and cUL listed






LED Vapor Tight – VPTLEDHO 2X4MX

The VPTLEDHO 2x4MX is an energy-efficient, LED Vapor Tight fixture designed for use in harsh environments. Ideal to operate in commercial, institutional, and industrial applications that require a watertight seal. This vapor tight fixture features 2′ x 4′ foot lengths, ideal for replacement and new construction, providing equivalent lumen packages to current fluorescent solutions, with significantly higher efficacy and reduced cost.

Tamper-resistant hardware mounting clips, along with standard gasketed seal and wet location rating offer an ideal light source for parking garages, livestock, car washes, refrigerated storage and food processing facilities, warehousing and manufacturing facilities.


  • Car Washes/Food Processing
  • Gas Stations
  • Livestock Locations
  • Laboratories
  • Industrial Facilities
  • Refrigeration/Freezers
  • Parking Garages/Utility
  • Warehouses/Supermarkets


  • Surge protector
  • White painted parts are treated with a five-stage phosphate bonding process and finished with high reflectance baked enamel
  • Low profile design optimizes shipping, storage and handing
  • Diffuser is secured continuously along luminaire sides
  • Polycarbonate lens, UV resistant
  • Toolless design driver cover snap into housing for easy installation
  • Performance engineered optical lens assembly delivers unique beam angles and reduces glare
  • High quality LED chips provide high efficiency, heat dissipation, stability, and lumen maintenance
  • Driver disconnect provided where required to comply with US and Canadian codes
  • May be surface or pendant (cable, hanging chain or stem kits) mounted
  • Class II driver,with 0-10V or Triac dimming



Recessed LED Troffer – CBLED

The CBLED provides a stylish modern design ideal for office and interior commercial applications.  

Utilizing a clear, prismatic polycarbonate diffuser prevents direct eye contact to the LED modules.  The edge design provides easy installation, mounting into standard 1” and 9/16” tee bars or screw slot grids. Two sizes are available with multiple lumen outputs. 


Aluminum frame with polycarbonate diffuser.


Universal driver, 0-10V, compatible with common dimming systems.


Unique composition provides a prismatic look.
Specifically formulated, frosted, prismatic acrylic lens provides a diffused luminance with the effective combination of excellent light transmission and haze.


Matte white, high reflectivity powdercoat finish.


  • All units bear UL label and are DLC listed. 
  • Standard 5 Year Warranty




8.54 CBLED Specification Submittal

Linear Architectual Wraparound – LAWLED

The LAWLED Linear Architectual Wraparound is available in 4’ LED Flat Board Array. The versatility of this high efficiency linear, contemporary-styled unit makes it ideal for classrooms, offices, corridors, laboratories, and any application where high efficiency, task appropriate illumination is essential.

For individual or continuous row mounting. Sufficient knockouts for surface or pendant mounting.


Die formed heavy gauge steel unitized into one piece.


Acrylic frosted.


Post painted in powder coated flat white polyester.


  • All units bear UL label
  • Suitable for damp locations
  • Made in U.S.A.
  • ARRA and BAA compliant
  • 5 Year LED Warranty

8.57 LAWLED sepc


Cut Sheet