800 Words: Lighting Facts, Energy Star and the DLC – Validation or Illusion

Posted: May 31, 2017 in 800 Words, General Commentary


Lighting Facts is a DOE funded program of information presentation specifically focused on LED products. Lighting Facts does not impose performance standards, it is designed to establish that data shown on the LF labels has been verified by certified test facilities.

Energy Star is an EPA program focused on interior lighting products, that establishes performance criteria as qualifiers for certification. The performance criteria include a wide range of performance metrics, including FCC compliance, power characteristics, and color consistency. All products must comply with current published specifications.

DLC QPL is a program of the Design Lights Consortium similar to ES in approach, qualifying product not included in the Energy Star program. By agreement, if ES covers a specific product, DLC is required to drop it. Products from older specifications remain in the QLP list, with no requirement to update imposed.

The value of these programs is to establish product performance credibility. All utilize the same core foundation: Certified lab testing and “off shelf” verification to enforce participant compliance.

Independent vs. Captive Certified Lab Facility Concerns

All programs require the use of NVLAP approved test labs. These can be independent or captive within the submitting manufacturer. Of 129 approved labs on the Lighting Facts web site (DOE approved NVLAP entities), there are 84 individual entities. Of those 84, 34 (40%) are lighting fixture manufacturer labs. While they are NVLAP certified facilities, they are not technically “independent”. There are three primary reasons this can be an issue.

  1. Manufacturer captive labs only test the products of their parent company. Independent labs have no built-in prejudice or loyalty. Certification of process does not guarantee lack of procedural bias.
  2. The performance of independent labs can be compared readily by anyone interested. This is not the case when considering manufacturer-captive labs that do not accept outside work.
  3. In-house labs are frequently used to test-tune-test-tune cycle products to create a desired test result – an expensive process when using independent paid-by-test service.

Off Shelf Verification Issues

Each of the certification and listing programs claim to use “off the shelf verification” to enforce the reliability of their included products. While this could have applied when the number of included products was small, as these programs have grown, this approach to verification is now essentially unrealistic. Lighting Facts now represents more than 1,500 manufacturers, with 55,000 products. There are now more than 215,000 products represented in the DLC list. A similar number is included in the ES program. Is “off shelf verification” applicable?

If we assume that there are 3,500 manufacturers (brands and sub brands), with 61 products each, for a total of 213,500 products, a statistical calculation that assumes 90% would be found in compliance, at a 95% confidence level would indicate that just 139 samples are required to establish verification. This is incorrect, as statistical sampling assumes the entire sample population to be of a uniform characteristic.

A more accurate sample rate would require consideration of individual manufacturers and volumes of products sold under each line item. Assuming 61 products listed, at 200 units per year, a confidence level to 80%, and uniform behavior across all listings – a minimum of 9 sample products from each manufacturer are required. Multiply this by 3,500 manufacturers = 31,500 samples required for verification, at a bare minimum. Further, considering most commercial products are made to order, reliably capturing “off the shelf” samples is virtually impossible.

Setting statistical calculations aside, the odds of capturing errant products “off shelf” from the volume of product delivered into the market is revealing. Based on 213,500 listed products x 200 per year, the total volume of units is 42,700,000. If we capture 1,500 of these for verification testing, making every effort to avoid multiple captures of any single product, the capture rate is just 1,500:42,700,000, or .003%. If just 10% of all products are out of compliance, the odds of capturing them are infinitesimal.


Lighting Facts is the least susceptible to verification problems as it focuses primarily on accurate product representation.

Energy Star is a valid program with strict performance requirements and demand for updates as new standards are published. The implications of being found out of compliance are the most severe of the programs covered here.

DLC is similar to ES overall. However, updates to the standards and allowing past listings to carry forward under older standards creates confusion and a state of unfairness in the process for new entries into the program, since older products of lower performance remain listed.

These programs are not illusion, but there are limits to their verification approach that needs redressing. The greatest value is that they are elevating the market by setting higher bars for manufacturers than they would set for themselves. Even if there is a modest percentage of non-compliant products, they will likely out-perform products from manufacturers not bothering to submit. Further, since few manufacturers want to be exposed as cheats, the majority of participants are likely making an effort to perform as promised.

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