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DLC Draft 1 Horticultural Technical Requirements V4.0

William Attardi on December 31, 2024

The DesignLights Consortium (DLC) has released their Draft 1 Horticultural Technical Requirements V4.0. The draft proposes three updates:

  • Efficacy increase: Hort V4.0 proposes to increase the efficacy threshold to 2.5 μmol × J-1, which is an 8.7% increase over the Hort V3.0 threshold. This will set the DLC efficacy threshold for LED-based horticultural lighting at more than 45% above the most efficacious non-LED option.
  • Removal of lamp categories: Hort V4.0 proposes to remove eligibility for lamps. This decision was made based on low application numbers in lamp categories.
  • Clarifications to various requirements: A variety of clarifications are proposed throughout Hort V4.0, including for definitions of key terminology and for certain testing requirements.

The Draft 1 Horticultural Technical Requirements V4.0 document is available here.

LightNOW: News and Opinion for the Lighting Industry

LED Bollards with Selectable Wattages by naturaLED

William Attardi on November 26, 2024

naturaLED® has LED Bollards with customizable wattage capabilities. 8″ diameter for easy retrofits and 4 configurations. Perfect for your area lighting, pathway, or perimeter lighting projects! BLD bright pathway lighting is important for the safety of pedestrian foot traffic. Ensuring that sidewalks and pavement are well-lit reduces the risk of people tripping and falling. The superior quality of our DLC Bollard light fixture provides glare-free lighting that replaces 100-watt metal halide fixtures and produces 2000 lumens. led bollards – naturaLEDWatch the Frank Grobmeier video: Discover the Difference between Pathway & Bollards (youtube.com)

The Statue of Liberty was made with copper but due to oxidation, it turned green.

When the “Lady in the Harbor” first arrived in New York in 1886, she didn’t look like the mint-green icon we know today. In fact, for the first twenty years of her life, she stood as a towering, metallic beacon of reddish-gold. Designed by French sculptor Frédéric Auguste Bartholdi and engineered by Alexandre Gustave Eiffel, the statue was a gift from France to America. To build her, Bartholdi chose copper for three practical reasons:

  • Malleability:It could be hammered into elaborate, thin sheets.
  • Weight:Copper is lighter than stone or bronze, making it easier to ship 350 individual pieces across the Atlantic.
  • Durability:It was strong enough to survive a 27-day ocean voyage and the harsh winds of the harbor.

When she was unveiled on October 28, 1886, her skin—made of 300 copper sheets roughly the thickness of two pennies—shone with a bright, metallic brown luster. The transformation from “penny-colored” to “patina-green” wasn’t planned. Bartholdi actually expected the statue to age into a deeper, darker red. However, the unique environment of New York Harbor—a mix of salt air, moisture, and industrial pollution—triggered a process called oxidation.

The Timeline of Change:

  1. 1886–1900:The bright copper dulled into a dark, muddy brown.
  2. 1903:The first hints of a light green crust, or “patina,” began to appear.
  3. 1906:The color change was so controversial that Congress nearly stepped in. They appropriated $62,000 to paint the statue back to its original color, but the public protested, calling the idea “sacrilege.”
  4. 1910–1920:The statue was a patchy mix of brown and green until 1920, when the oxidation was complete, leaving her entirely teal.

While we now view the green color as iconic, it actually serves a vital structural purpose. The layer of verdigris (the green patina) acts as a protective shield. It seals the copper underneath, preventing the metal from further corrosion and weathering.  By the time the color fully changed, a new generation of immigrants had arrived in America seeing a green statue.