Solid State Lighting FAQs

Solid-State Lighting FAQs

The FAQs below represent answers to common questions about submitting a product to the DLC Solid-State Lighting QPL and how our requirements and policies are interpreted. They are explanatory only and should be viewed as such. In all cases, please refer to the Terms of Use for the operative rules regarding participating in the DLC QPL.


DLC Background

DLC publishes manufacturer and model identifying information, as well as verified tested performance or rated performance information for each product. These fields include:

  • Manufacturer
  • Brand
  • Model Number
  • Luminaire Efficacy
  • Light Output
  • Power Factor
  • Correlated Color Temperature
  • CRI
  • Wattage
  • Dimming Information
  • Light Distributions (i.e., zonal lumen density, NEMA classification, and/or spacing criteria)

The DLC team will first notify you that the application has been received via email. A DLC reviewer will review your application(s). It takes about two weeks to complete the review of your application from the time payment of the application fee is confirmed.

Upon completion of the initial review, a DLC reviewer will contact you to let you know if your product passes, fails, or requires additional clarification or application materials to determine qualification.

  • If additional application materials are required, you must provide the DLC reviewer with an estimate of when the additional information will be available and abide by the timeline established. Review of the application will commence when the additional materials are received and the application is considered complete.
  • If all documentation is provided and the product meets the Technical Requirements, the DLC reviewer will let you know that the product qualifies and the product will be listed on the QPL. If all documentation provided demonstrates the product does not meet the Technical Requirements, the product fails. The DLC reviewer will provide detailed information regarding which metrics did not meet the Technical Requirements. Any design changes made to the product after the initial review will require a new application and application fee.

The "Technical Requirements Version Number" field indicates the version of the Technical Requirements Table to which a listed product was evaluated when qualified. The Technical Requirements Version Number does not indicate whether or not a product meets a the most recent set of requirements, nor does it indicate if a product will be delisted during a specification transition process. Whether or not a product is delisted during the specification transition process is dependent on the performance data associated with the listing, as it compares to the current Technical Requirements, not the Technical Requirements Version Number. For example, if a product is initially listed with a previous Version Number of the Technical Requirements Table on the QPL, but meets all the Technical Requirements of next Version Number, the product will not be delisted at the end of the grace period established during the announcement of the new version of Technical Requirements. Similarly, if a product was initially listed with a previous Version Number and remains listed when a new Version Number is released, that indicates that the product is considered listed under the new version.

If your product is published on the QPL, you may market the product as DesignLights Consortium® qualified. Please refer to the DLC’s Logo Guidelines for instructions on proper marketing of a DLC qualified product.

Each DLC Member has access to the QPL and makes its decision about what products to incentivize based on its own program parameters, including cost-effectiveness tests. Manufacturers should work with utilities/energy efficiency program sponsors on a project-by-project basis to have their products be eligible for rebates. Please note that listing on the QPL is not a guarantee that the products will be eligible for incentives from DLC Members. Any incentives or other rebates are entirely at the discretion of the particular energy efficiency program sponsor.

The fee is $500 per Single Product Application to cover the technical review and administrative costs. The Single Product Application fee covers additional family members if the variations of those family members are limited to higher CCT, dimming variations, or variations that do not affect the performance of the product (mounting, housing color, etc). Family Grouping Application fees are dependent on the group of products submitted for qualification. Please see the Application Fees page for more details. A DLC reviewer will review the product family, determine the application fee, and confirm payment details with the manufacturer.

Credit card payments are preferred, though if that is not possible, you may pay by check. Follow the instructions on the Invoices page once logged into your manufacturer account if submitting a check. Please note that if you pay by check the DLC reviewer cannot process the application until your application is complete and payment is received.

The DLC does not endorse any laboratory meeting the DLC Testing Laboratory Requirements. Laboratories representing the ability to qualify products and laboratory test reports indicating product performance meets DLC Technical Requirements do not represent official DLC product qualification. All decisions regarding product qualification are made by the DLC. DLC reviewers reserve the right to request documentation to clarify testing conditions or to confirm testing has been conducted by a laboratory that meets these requirements at the time of testing.

Eligibility

If a manufacturer wishes to update a qualifying product at a new voltage operating range (for example, to 120-277V, on a universal driver), the manufacturer will need to provide the additional data to demonstrate that the worst-case conditions in regard to efficacy and power quality pass the requirements (i.e., submitting another LM-79 at 120V if it was previously submitted with only an LM-79 at 277V). Because of the review needed to evaluate the additional test reports, the manufacturer must submit an additional application fee. The manufacturer should contact its DLC reviewer before submitting the payment to avoid creating an entirely new application.

In reference to this particular primary use designation, the DLC is agnostic to how the product is marketed, as long as the minimum requirements are met, including base type.

The eligibility of UL types varies across lamp types and categories as outlined in the latest technical requirements. Lamps which are marketed to operate utilizing magnetic ballasts are not eligible regardless of lamp category and type, and regardless of UL operation type.
 
UL Type B and C products marketed to replace T12 lamps (either solely or as a lamp intended to replace either a T8 or a T12) – are eligible in the 4-foot and 8-foot general applications. UL Type A lamps marketed to replace T12 are not eligible regardless of length or general application (including 4-foot and 8-foot). Lamps claiming to replace T12s in any other general application (2-foot, 3-foot, U-bend) are not eligible. Lamps marketed to replace any other designation of fluorescent lamp are not eligible.

The 4-foot representative fixture must be a genuine product marketed and produced by the same manufacturer and have a distinct model number. The LED board of your 4-foot fixture should have no variance in the quantity, layout, or spacing of LEDs as half of your 8-foot fixture. The two lamps must also have the same type and quantity of driver(s) operating at the same drive current, and must also be of identical construction having identical cross-sections, the same tube material and thickness, and same heatsink material and extrusion.

One-lamp Type C TLEDs and one-lamp Type C 2G11-base lamps are eligible for qualification in all general applications within the Linear Replacement Lamp and Four Pin-Base Replacement Lamps for CFLs categories, respectively. This includes T8 2-foot, 3-foot, 4-foot, and 8-foot replacement lamps, T5 and T5HO 4-foot replacement lamps, U-bend replacement lamps, and Type C 2G11 base lamps.

In addition to the lamp-level testing as specified, lamps must be tested in a reference luminaire. Applicants must test 1-lamp systems in one of the configurations listed in the relevant section of the policy. Specifically:

  • Two-foot T8 replacement lamps must test with 2, 3, or 4 lamps installed in the reference luminaire
  • Three-foot T8 replacement lamps must test with 2 or 3 lamps installed in the reference luminaire
  • Four-foot T8 replacement lamps must test with 2, 3, or 4 lamps installed in the reference luminaire
  • Four-foot T5 replacement lamps must test with 2, 3, or 4 lamps installed in the reference luminaire
  • Four-foot T5HO replacement lamps must test with 3, 4, or 6 lamps installed in the reference luminaire
  • Eight-foot T8 replacement lamps must test with 2 lamps installed in the reference luminaire
  • U-bend T8 replacement lamps must test with 2 or 3 lamps installed in the reference luminaire
  • 2G11-base replacement lamps for CFLs must test with 2 or 3 lamps installed in the reference luminaire

Products should apply under, and will be listed on the QPL under, the primary use designation corresponding with the configuration of lamps used in reference luminaire testing. Single-lamp systems will note that they are single-lamp Type C systems under the “Notes” field in their listing information.

The DLC evaluates reported performance claims based on the information manufacturers choose to report in their product specification sheets and/or other marketing materials. If the performance claims reported in specification sheets and/or other marketing material are below the Technical Requirements, the DLC reviewer will reject the application as marketing material cannot indicate that the product’s marketed performance is below any of the Technical Requirements. To avoid delays in review, please review all marketing material prior to submitting an application to ensure it accurately reflects the product submitted, and does not contain outdated or incorrect information, or typographical errors. Please note that in addition to evaluating reported performance claims in specification sheets, the DLC will also conduct a technical review of a product’s performance via the required test data detailed in the Single Product and Family Grouping application instructions.
 

Yes. Both G24q-1, G24q-2, and G24q-3 and GX24q-1, GX24q-2, and GX24q-3 base types are eligible under either the Vertically- or Horizontally Mounted Four Pin-Base Replacement Lamps for CFLs General Applications.

Yes, luminaires intended to provide lighting for outdoor sports fields are eligible as Architectural Flood and Spot luminaires. Products intended for illuminating sports fields may also apply under the Specialty provisions if they desire. Please review both the Architectural Flood and Spot luminaires Technical Requirements as well as the provisions for applying under Specialty designations before applying.   
 

The General Application, or light output bin (low-, mid-, high-, or very high-output), is determined based on the total lumen output of the luminaire. Although DLC evaluates lumen output and efficacy based on the lumen output in the 0-90° zone, total lumen output and total efficacy is listed on the QPL. Therefore, the General Application is determined based on the total lumen output to be consistent with the information published on the QPL. See requirements for Non-Cutoff and Semi-Cutoff Wall-Mounted Area Luminaires under the Technical Requirements for more details on evaluation the performance of these products.

No, Four Pin-Base Replacement Lamps for CFLs that are capable of operating off both the existing ballast (UL Type A) and line voltage (UL Type B) are not eligible. Per the Four Pin-Base Replacement Lamps for CFLs policy, only "Plug and Play" (UL Type A) replacement lamps are eligible for qualification at this time.

No. The linear replacement lamp categories are intended for LED replacements to standard two-foot or four-foot linear replacement lamps. Products that are intended to function as two lamps combined together are not eligible for qualification at this time. This includes products with 4 pins at each end, as well as products which appear to be two lamps welded together. Below are some examples of products that are not currently eligible under the linear replacement lamp categories.

Yes. Luminaires intended to provide illumination to the facade of billboards are eligible as Architectural Flood and Spot or Landscape/Accent Flood and Spot Luminaires. These products are NOT eligible for the Outdoor Pole/Arm-Mounted Area and Roadway Luminaires category. Remember to review the Technical Requirements Table for each category to determine if your product would meet the listed requirements before applying.

These type of products are no longer eligible under the Specialty provisions with this generic end-use descriptor. For niche end-use applications of wall-mounted exterior lighting that specifically require significant amounts of light in the uplight or glare zone, DLC will consider requests for qualification of these products under the Specialty provisions on a case-by-case basis. In these cases, a specific end-use (and associated descriptor) must be identified that is distinct from the definition and intention of the non-Specialty PUD. Documentation will be required to demonstrate the marketing and use of products in these niche applications. Products currently listed as Specialty: Non-Cutoff Wall-Pack will be reviewed for compliance with the Non-Cutoff and Semi-Cutoff Outdoor Wall-mounted Area Luminaires PUD, and products that meet the requirements, will be transitioned. Products that do not meet the requirements will need to demonstrate a specific end-use and associated descriptor that is different from the definition of Non-Cutoff and Semi-Cutoff Outdoor Wall-mounted Area Luminaires PUD. If the request is denied, the products will be de-listed from the QPL.

No. At this time, products that incorporate removable or replaceable lamps are not eligible for qualification.

The warranty must cover the complete luminaire, or retrofit kit/replacement lamp when applicable, for a period of at least five years. Warranties that only cover certain components of the luminaire or retrofit kit/replacement lamp are not sufficient to meet the requirement. Warranty statements are reviewed on a case-by-case basis and the DLC reserves to right to seek additional clarification if necessary.

The warranty must cover all components of the luminaire for a period of at least five years. Warranty documentation must clearly explain the terms and conditions associated with the warranty. Note that the “luminaire” includes light source, housing, heat sink, power supplies and other electrical components, optics, and any other components of the luminaire.

The LED Package Part number describes the LED, color (e.g., white), CCT (e.g., warm white), and other characteristics of the LED. Every LED must be specified with a complete LED Package Part number (e.g., XPEWHT-L1-XXX-XX-X-XX). This specific part number must be consistent throughout the application and supporting documentation, such as the LM-80 report.

No. The manufacturer name listed on the QPL must match the manufacturer name used in marketing materials. If a manufacturer wishes to change their manufacturer name listed on the QPL, they will be responsible for demonstrating the new manufacturer name is used throughout marketing materials, website literature, etc.

If a product has any functionality that enables it to change the color (i.e. CCT) of the emitted light, the intention is for it to be eligible under the requirements for color-tunable products. This includes products with a small set of color temperature settings controlled through mechanisms such as dipswitches set at the distributor or by the installer. Such products will not be deemed as non-color-tunable.

No two model numbers can be listed under the same product category on the QPL for one given manufacturer. If a manufacturer submits the same model number for multiple products, the DLC reviewer will insist the manufacturer make some distinction in the model numbers that represent the variations of the product. The utility and consumer must be able to identify the differences between products from the model number listed on the QPL.

No. The Horizontal and Vertical Refrigerated Case Luminaire categories are intended for complete luminaires, which by definition, cannot use the existing mounting mechanism of the incumbent technology. To ensure only complete luminaires are submitted under this category, with all applicable drivers/power supplies and mounting mechanisms required of a luminaire, products that incorporate pin-bases are not eligible under these categories at this time. DLC staff reserve the right to ask for additional information about the product to verify that the product is sold as a complete luminaire.

Products marketed for or intended for temporary usage/installation are not eligible for DLC qualification due to the complications in determining savings from non-permanent products. Products not specifically marketed for temporary usage, but that have a form factor similar to products that are marketed for temporary usage, are also ineligible. These types of products have typically been marketed as “work lights”, “construction lights” or “job lights”,  which are designed to hang temporarily from a clip or hook or placed on the ground during construction, and are then moved to a different location. Example of Temporary Work Light

This policy is not limited to work lights, but any products that also imply the product is not intended to be installed permanently.

 

Application Requirements

No. The DLC requirements state that products within a family group of white-tunable products must have the same types of LEDs, and an identical technological approach to color output. This is intended to include a restriction that all products within a family group have the same tunable range. Therefore, as an example, if one version of a product can tune from 2700-5000K, while another version can tune from 2200-6500K, they must be submitted under separate applications, with independent testing.

If submitting a Single/Family application where the safety documentation involves a multiple listing document, please submit the private labeler compliance certificate and populate the Application Form with the safety organization and private labeler safety file number. If the safety organization has not provided a private labeler compliance certificate, one will need to be obtained from the safety organization in order to proceed with the Single/Family application process.

Yes. As of Technical Requirements V4.3, implemented on March 26, 2018, providing safety certification documentation is required for all types of Update Applications. Please refer to the Safety Certification page for more information on what safety certification documentation is required.

No. Per the Linear Replacement Lamp Requirements, lamps that require the use of specialized accessory components in order to meet the stated requirements are not eligible for qualification. The DLC reserves the right to ask for additional information regarding any components included in the testing with the product submitted, and deem a product not eligible for qualification.

Examples of specialized components that are not eligible include the use of socket extenders to shorten the distance between lamp holders and changing the lamp holders from G13-base to G5 base, or vice-versa. However, replacement of the existing fluorescent troffer sockets is allowed, and not considered a specialized component, if the replacement is specifically to change the lamp holders from shunted to unshunted, or vice versa, for safety compliance.

If the incorrect information in the LM-79 or ISTMT is first identified by the applicant, unprompted by the reviewer, the DLC will accept a revised test report. All test report revisions must follow the rules set forth by the accreditation body. If the incorrect information is first identified by the reviewer, the DLC will not accept a revised test report, and will require the product to be retested. In the event of a retest, the DLC will only reevaluate the new, retested data. Data issues encountered in LM-80 reports will be handled on a case by case basis. The DLC urges all applicants to thoroughly review all application documentation prior to submittal to ensure all information submitted is accurate.

In the event that the test report contains failing test data that is not representative of the products performance, please see the FAQ, “I believe that the test report I submitted with my application does not represent my product's performance. Will the DLC accept a new report with different performance on the same product design?”

No. In the event that the test report submitted does not meet the Technical Requirements, the DLC will not accept a revised test report unless a design change has been made to the product. Please note that the Self Certification Statement provided which each application includes language that the applicant certifies all model numbers submitted meet minimum requirements. In the event where a manufacturer chooses to make a design change to the product, and resubmit test data that represents that design change, the DLC will need detailed explanations of the changes made as well as assurance that the changes will be reflected in all products sold. If choosing to make a design change, the manufacturer must create and submit a new application, and pay the associated application fees for the review of the redesigned product(s). If a test report submitted does meet the Technical Requirements, but includes incorrect information, please see FAQ, “I submitted a test report that meets the Technical Requirements, but noticed that there is incorrect information reported. Will the DLC accept a revised test report?”

When submitting an application containing White-Tunable products, the Scaled Performance Table must be populated with the performance data representative of the least efficacious setting of each product seeking qualification. For more information regarding White-Tunable applications, please refer to Testing and Reporting Requirements for Color-Tunable Products.

Yes, under specific circumstances. Configurations of multiple luminaires mounted on a singular mounting structure can be listed in one line item on the QPL, provided that each mounting configuration includes only identical luminaires, and the configuration of luminaires is identifiable in the ordering code nomenclature. This provision is only applicable for products within the Outdoor Pole/Arm-Mounted Area and Roadway Luminaires, Outdoor Pole/Arm-Mounted Decorative Luminaires, Landscape/Accent Flood and Spot Luminaires, and Architectural Flood/Spot Luminaires Primary Use Designations.

Additionally, products that wish to utilize this listing approach must be submitted via a Family Grouping application. An example of a product design that would be eligible for bracketing includes a pole-mounted area luminaire that can be ordered in configurations of 1, 2, 3, or 4 luminaires mounted to a singular pole. In this example, the 1, 2, 3, and 4 luminaire configurations can be bracketed within a singular model number. The form of the model number should be submitted as:

  • ABC-123-[1, (2, 3, 4 see notes)]

The “Notes” field on the QPL will then state:

  • “Available in configurations with multiple identical heads where model number indicates 1=1 fixture, 2 = 2 fixtures, 3 = 3 fixtures, 4 = 4 fixtures”, etc… – as needed based on specific number of configurations offered using identical fixtures.

No. While the DLC does not require testing in all approved and pre-approved housings available for each retrofit kit or replacement lamp Primary Use, the approved and pre-approved housings selected for testing are intended to provide similar, common environments for which the retrofit kit may be installed in the field. As such, it is the DLC's expectation that the submitted retrofit kit should meet the requirements regardless of the housing chosen for testing. If testing is provided showing that the product does not meet the requirements in a specific housing, the products will not be able to be qualified and listed on the QPL. For additional information regarding the resubmission of test data on the same product design, please refer to the following FAQ

Because they have different light output and distribution requirements, center and end units for vertical refrigerated case lights may not be submitted in the same single product application. They should either be submitted as separate applications, or applied for under the family grouping policy. Family groups that include both center and end units must demonstrate compliance with the requirements on worst-case light output of both center and end units.

All Stairwell/Passageway Lighting must be capable of at least bi-level dimming. Graduate dimming is acceptable, as long as the controls dim the fixture to a lower-power state when the space is not occupied. Documentation of dimming and controls must be provided with the application.

All occupancy sensors for the Stairwell/Passageway Lighting category are acceptable, as long as they meet the following requirements:

  1. Luminaires that include integral controls for occupancy sensing and bi-level dimming.
  2. Luminaires that operate off remote occupancy sensors, including wireless options, where a remote sensor(s) is sold packaged together with a luminaire(s) under a single model number or ordering code.
  3. Luminaires that operate off remote occupancy sensors, including wireless options, where the luminaire and sensor are sold separately, but the luminaire has features enabling communication with a remote sensor(s).

If a manufacturer wishes to update the listed performance of a qualified product, the manufacturer must provide new test data for the updated product and pay the associated application fee. This will require DLC review. If the manufacturer wishes to have the originally qualified and updated products both listed on the DLC QPL, a new part number for the updated product must be provided to avoid duplicate model numbers on the QPL. If model numbers are not changed, the listing will be for the upgraded product only. Multiple products with identical model numbers may not be listed under the same product category on the QPL.

Understanding the available options for a product is necessary to ensure worst case performance has been identified and tested. As such, an explanation of the ordering code/model number breakdown must be included in the relevant section of the Application Form and must match the spec sheets and other marketing materials submitted with the application. DLC reviewers reserve the right to request additional information or clarification of ordering codes or model number breakdowns. Please note that omitting or submitting an insufficient ordering code/model number breakdown explanation is one of the most common reasons application reviews are delayed.

Acceptable forms of signatures include either a wet signature or verified digital signature. The signature must be affixed to the document, unable to be moved. Wet signatures must be written on a print-out of the document with a pen, then scanned and submitted. Verified digital signatures must authenticate the electronic user and capture the user’s intent to sign the document. Software may not auto-sign on a signee’s behalf.
 

There are no color temperature limitations regarding the color-tunable feature for standard product listing on the QPL. However, the existing Technical Requirements specific to the product type must be met. For instance, outdoor products are not limited to a color temperature range but must be capable of light output at  ≤ 5700K (per the nominal ANSI binning descriptions). Please consult the Technical Requirements for color temperature specific to the General Application and Primary Use Designation under which the product will apply.

Yes. DLC expects that manufacturers provide the most up-to-date LM-80 report available for the LED package/module/array used within the product. It is the submitting manufacturer’s responsibility to ensure they have received the most up-to-date LM-80 report from the LED manufacturer for each application. Additional data that improves the projection accuracy cannot be ignored simply because it shows worse performance. 

For products intended to operate on regular Alternating Current systems, the “Minimum Input Voltage” and “Maximum Input Voltage” fields in the Application Form are intended to report the rated nominal AC input voltage range the product is designed to operate on. For UL Type A replacement lamps, these fields should be left blank, or indicated as “n/a”, as the input voltage is a property of the fluorescent ballast(s) the lamp is designed to operate on, and not of the lamp itself. For Dual Mode (UL Type A and B) products, these fields should record the AC voltage input range for which the product is designed to operate as a Type B replacement lamp.

In situations where the originally-provided drive current information impacts whether or not the product will meet the lumen maintenance requirements, revised drive current information will typically not be accepted, unless the product is redesigned, retested, and resubmitted. The DLC reserves the right to review changes to drive current that impact eligibility on a case-by-case basis to determine whether revisions without a redesign are acceptable. This supports efforts to maintain the integrity of the product data listed on the QPL.
 
Please note that in all situations, it is expected that the drive current information within the Application Form accurately represents that product's performance. The Self Certification Statement provided with each application includes language that the applicant certifies all model numbers submitted meet minimum requirements and that the information provided in the application is accurate.
 
In the event where a manufacturer chooses to make a design change to the product and resubmit test data that represents that design change, the DLC will need detailed explanations of the changes made as well as assurance that the changes will be reflected in all products sold.

The Outdoor Pole/Arm-Mounted Area and Roadway Luminaires and Outdoor Wall-Mounted Area Luminaires category are designed for luminaires intended to light up general areas. The Architectural Flood and Spot Luminaires category is designed for luminaires intended to light up specific items/objects/elements. The floodlight category cannot be used to qualify area lights that would not meet the zonal lumen requirements of the Outdoor Pole/Arm-Mounted Area Luminaires or Outdoor Wall-Mounted Luminaires category. See examples of these Primary Use Designations on the Product Eligibility page.

No. The DLC is interested in the performance of the production-ready product seeking qualification. As such, test data on prototypes will not be accepted for DLC submissions. Testing must be on production-ready models that are identical in design and construction to those that are being or will be sold.
 

Testing

For white-tunable product submissions, manufacturers must report the performance for their least-efficacious product within their group according to Table 1 in the requirements. Performance must be reported for one point within each ANSI quadrangle the product is able to tune to. The language in the policy is not intended to state that performance must be reported for the highest CCT and lowest CCT within each quadrangle, but rather one point in each quadrangle from the lowest CCT to the highest CCT the product can tune to.

Yes. Production-ready models that are identical in design and construction to the other product variations in the family, but differ in a measurable parameter to represent a worst case performance metric (i.e. worst case thermal member), can be included in a Family Grouping application if the corresponding test data is provided. For example, this is commonly seen in products with a higher LED drive current than what is intended to be offered to customers to represent the worst case thermal member. A description of the testing rationale is required, and may require additional details during the review.

Note that there may be additional implications if any of the products described above cannot be procured for Surveillance Testing purposes. For instance, if one of these worst-case brackets is selected for Surveillance Testing but cannot be procured by the DLC, then the product will be de-listed in accordance with the Surveillance Testing Policy. In this situation, the remaining family members would need to be re-bracketed or the entire family may be de-listed. It is up to each manufacturer to weigh the advantages and disadvantages associated with including non-procurable worst-case product brackets.

Manufacturers should always be considering worst-case across all product variations, including input voltage, before submitting test data to the DLC. However, in the event that the electrical testing demonstrates a higher wattage at a different voltage than the photometric testing was conducted, the DLC will allow worst-case efficacy to be calculated from taking the lumen output from the photometric testing and dividing by the higher wattage from the electrical testing. This calculation approach is permitted to reduce testing burden rather than requiring the manufacturer to retest light output at the worst-case operating voltage. This approach is only allowed when the only variable between the LM-79 lumen output test and the electrical test is input voltage, and is based on the premise that the driver output (and therefore lumen output) will not significantly change with input voltage. If using the calculation approach, the DLC reserves the right to ask additional questions to confirm the input voltage is not impacting the drive current to the LEDs before moving forward with the review. The calculated efficacy will be listed as the Measured Efficacy on the QPL. If the manufacturer chooses to retest at the worst-case operating voltage instead of conducting the calculation, the retested values will supersede any calculations. 

Please refer to the guidance and links on the Testing Lab Requirements page on the DLC website.

No. To remain fair and consistent across manufacturers submitting applications to the DLC, the DLC must strictly enforce its policies and cannot make ad hoc exceptions, even if there is a sound technical justification for the alternate approach to testing. In situations where the testing does not follow DLC policy, the DLC will require the product be retested according to policy, or may decide that the product is ineligible if retesting according to policy is not a viable option.

Policy revisions occur periodically. For more information on past and present policy development efforts, please see Policy Development. The DLC is very open to suggestions for policy revisions; if you have a suggested revision to a policy, please submit the request to info@designlights.org for consideration during policy development cycles.

Please note that clarifications to existing policies can be found via this FAQ page.

In reviewing Pre-approved Equivalent requests, the DLC is verifying that the requested incumbent fixture is/has:

  • Commonly used in the application category for which the retrofit kit is applying
  • Specifications that align with the application category for which the retrofit kit is applying
  • Similar thermal environment (i.e. internal volume and construction materials) to those listed under the Approved section of each Primary Use

If the above information is not clear in the spec sheet provided for the requested fixture, the DLC will require additional information to ensure the requested fixture aligns with the Approved fixtures of that given Primary Use. Pre-approved Equivalent requests may be sent to applications@designlights.org.

Yes. Due to the system-level testing configuration acceptability (see Testing Notes under Testing & Reporting Requirements for Linear Replacement Lamps) of Type C Linear Replacement Lamps, THD and Power Factor measurements will be accepted when measured inside the appropriate reference troffer if bare-lamp electrical testing is not available. Please note that this consideration only applies to Type C Linear Replacement Lamps, where more than one lamp is powered by a dedicated driver.

Testing must be conducted at each end of the acceptable voltage range of the ballast.

Any variation that would affect electrical compatibility with the existing CFL ballast must be tested for compatibility. This means that wattage variations and dimming variations need compatibility testing, while CCT or optic (beam angle) variations do not. Feedback on the application of family grouping rules is welcome; please contact info@designlights.org.

Luminaire efficacy should be reported as the total luminous flux from the fixture divided by the total input power. Luminous flux is based on the photopic luminous efficiency function (V lambda), not scotopic or mesopic efficiency.

Efficacy, power factor, and THD are calculated based upon the complete system required to install the product. The system may include an internal driver, an external driver, and/or an instant start ballast depending on the product submitted.

It is the manufacturer’s responsibility to determine the “worst case” product of the group/sub-group. The worst-performing product can be identified through engineering analysis and/or in-house testing of all family members. If engineering analysis is used to identify worst case, the tested value associated with the worst-case product may be higher than scaled values indicating the performance of other family members. If this is the case, the manufacturer must provide an explanation that addresses the variance between scaled values and tested values, and the reviewer must understand the manufacturer’s scaling method before the application process may continue.

Yes, it is acceptable for manufacturers to install the thermocouples themselves as long as it does not alter the thermal characteristics of the luminaire housing.

The schematic diagram is used to verify that the TMP measured in the ISTMT conforms to the LED manufacturer-specified TMP location. The ISTMT report must include a photograph of the tested TMP for the DLC reviewer to compare with the schematic diagram of the TMP specified by the LED manufacturer.

In general, full LM-80 results are necessary for DLC qualification. However, manufacturers may submit products using an LED package/module/array where limited LM-80 data is available if the following conditions are met:

  1. The LED package/module/array is a successor package/module/array to a previous generation package/module/array according to ENERGY STAR® Program Guidance Regarding LED Package, LED Array and LED Module Lumen Maintenance Performance Data Supporting Qualification of Lighting Products.
  2. The manufacturer provides the complete (≥6,000 hours) LM-80 of the previous generation LED package/module/array.>
  3. The manufacturer provides at least 3,000 hours of LM-80 data of the successor LED package/module/array.
  4. The successor package/module/array data demonstrates better performance at 3,000 hours than the previous generation LED package/module/array data at 3,000 hours.
  5. The manufacturer provides the remaining 3,000 hour successor LED package/module/array data when available.

Consistent with guidance from ENERGY STAR, while there may be several acceptable locations to measure the temperature of the LED package/module/array (collectively referred to as the TMPLED), the TMP in the ISTMT must match the TMP used during the LM-80. If the ISTMT TMP does not match the LM-80 TMP in the original submission material, DLC staff will look for the applicant to provide one of the following options:

  1. Provide an LM-80 of the board or module, where the TMP is monitored/measured at the same TMP used in the ISTMT.
  2. Provide an ISTMT measuring the TMP of the hottest LED in the product at the same TMP used in the LM-80.

If neither of the above is possible, and the LED TMP is not accessible, DLC staff will work with the manufacturer to obtain information that explicitly describes the relationship between the board TMP and LED TMP. However, this information will be reviewed on a case by case basis, and may not be sufficient to appropriately verify compliance with the lumen maintenance requirements for all applications.

Rotatable end cap linear replacement lamps should be tested in the orientation specified as the default in the manufacturer's installation instructions. If the installation instructions do not specify an orientation, the lamps should be oriented “straight down” (this is commonly the “zero degree” setting). DLC reviewers will review the installation instructions provided with the application to verify the appropriate testing orientation, and compare this against documentation in the LM-79 report and IES file. Rotatable end cap linear replacement lamp listings will include information on the testing orientation in the Notes field. For more information on the Linear Replacement Lamps Policy, please click here