Qualify a Fixture

Horticultural Family Grouping Applications

The DLC allows family grouping applications for horticultural lighting products starting with the V2.0 Technical Requirements effective date (March 31, 2021). Family grouping applications are designed to reduce the total testing and application fees required to list groups of products that comply with the family grouping definition. Typically, parent products are based on tested data from worst-case models within a family group, and child products are based on reported data. Generally, limited testing can be provided if the worst-case models demonstrate compliance with the Technical Requirements.


To submit a family grouping application, a product family must meet the following definition:

  • A family may contain a single LED package/module/array, a standardized set of LED packages/modules/arrays, and/or variations in standardized sets of LED packages/modules/arrays.
    • Families comprised of different models that correlate to fixture-level variations of spectral distribution will be grouped in spectral sub-groups.
      • Spectral sub-groups are defined as distinct product offering spectrum variations within the family. This is commonly shown on specification sheets as a “light color” or “spectrum” options.
    • Child products are required to emit the same relative Spectral Quantum Distribution (SQD) as a representative parent. If not the same relative SQD, a separate spectral sub-group is required.
      • The DLC acknowledges that different lumen packages, optics, etc. can cause small changes to SQD. These variations do not typically result in different spectral sub-groups. However, differences that result from changes to specific LED type, relative quantities of LEDs, etc., do specifically require spectral sub-groups or separate family grouping applications.
      • To limit testing burden, SQD images generated from parent-level spectral data will be used to represent child products.
    • Products employing multiple types of LEDs – that is, those that are not dual-sourcing and/or utilizing ‘equivalent’ LEDs – are eligible, so long as the construction, types, and quantities of the LED packages/modules/arrays are documented.
      • An LM-80, ISTMT, and TM-21 projection is required for each type of LED present in the product. As per normal testing rules, ISTMTs should measure the applicable temperature measurement point (TMP) and must be conducted on the hottest LED of each type.
      • Each LED must demonstrate the required Q90 ≥ 36,000 hours, with exceptions noted in the Testing and Reporting Requirements for LED-based Horticultural Lighting V2.0 policy.
      • If variable numbers of LEDs are dynamically chosen, and therefore the precise construction of any given product is not defined, the products are not eligible for family grouping applications. Policy development for appropriate evaluation of this type of product is under consideration.
    • Products employing varying output channels beyond simple, single-axis dimming of the whole product (i.e. spectrally-tunable products) are eligible so long as testing and reporting requirements as described in the “Special Considerations for Spectrally-Tunable Devices” subsection of the Testing and Reporting Requirements for LED-based Horticultural Lighting V2.0 policy are satisfied.
  • The family must demonstrate scalability or modular use of the identical LED packages/modules/arrays, electronics, optics, heat sinking, and any other applicable features employed in the fixture.
  • Provided that the impact on performance is well understood and explained by the applicant, other design parameters and components, such as electronics, optics, heat sinking, and other performance-affecting and non-performance-affecting features, are typically allowed to vary. The DLC reserves the right to request additional information confirming that these features do not affect performance.
  • A family may contain multiple driver variations as well as different LED drive currents achieved by a programmable driver. Please refer to the testing requirements for fixtures with multiple drivers described in the Testing and Reporting Requirements for LED-based Horticultural Lighting V2.0 policy for specific instructions.
  • The overall physical fixture housing and assembly of the fixtures in the family group must be of identical material and construction, and may only differ in overall physical dimensions for different models within the grouping.
  • A family may contain variations in fixture mounting systems provided that the mounting systems do not change thermal management characteristics.
  • In all application submissions, manufacturers must list full and complete model numbers that clearly demonstrate all fixture options offered in the family grouping.
    • “Full and complete model numbers” means model numbers that include all performance-affecting and non-performance-affecting variations offered, and which do not omit any option that is available to customers in the market. In general, options that do not affect the performance of the fixture can be submitted as a single model number with multiple options bracketed in the model number. For example, a fixture that has multiple non-performance-affecting mounting options may include all mounting options in brackets (e.g. “[M1, M2, M3]”). Low and high voltage options may be submitted as a single model number (e.g. “ABC PAR [120V-277V, 347V-480V] M1”) with the worst-case performance reported. Multiple or alternate drivers may also be listed in a single model number as long as the drivers perform nominally the same. If the alternate drivers perform nominally differently (that is, they are not presented to customers as having the same performance other than input voltage, and result in different ordering codes) then the unique drivers must be listed in separate model numbers. Options that affect photosynthetic photon flux (PPF) output, presence or lack of fans, dimming, or spectral tuning capabilities, etc. may not be bracketed and submitted as a single model number.
    • DLC reviewers may check web listings and other marketing materials and reserve the right to request additional information to document the full and complete model number. A lack of clarity in model numbers will result in delayed application processing. Misrepresentation of model numbers discovered outside the application process will generally be considered a violation of the DLC program rules and Logo and Trademark Use Guidelines.
    • Each model number may only represent the fixture under a single brand. If the fixture can be sold under multiple brands, model numbers must be listed separately for each brand.
  • Decisions on whether a given group of fixtures are eligible to be submitted in the same family grouping application are at the sole discretion of the DLC. Variation in materials, designs that change the position of key components relative to one another, and other variations that, by the judgement of the DLC, have potential to cause differences in spectral, optical, electrical, or thermal performance, will not be allowed within the same family group or spectral sub-group, as appropriate.

Please review the V2.0 Testing and Reporting Requirements for additional policy clarifications and contact horticulture@designlights.org with any questions about submitting an application to the DLC.

Testing Family Grouping Products

The family grouping testing policy is designed to reduce testing burden as well as to reduce the total application fees required to list groups of horticultural products, as compared to listing products individually. By identifying the models with the worst-case performance within a family group, limited testing can be provided if the worst-case models demonstrate compliance with the Technical Requirements.

Application Instructions

  1. Determine if your product is eligible to be qualified by the DLC and meets the Technical Requirements.
    • See the Technical Requirements to determine whether your product meets DLC minimum performance requirements.
    • Review Testing Lab Requirements to ensure your product has been properly tested.
  2. Create a Manufacturer Account.
    • If you have not done so already, create a manufacturer log-in. The DLC recommends that the application be completed by a person with technical knowledge of lighting products and testing, such as a product engineer. Experience has shown that applications submitted by non-technical staff may lack important details which can delay overall processing.
  3. Complete the Product Application Form.
    • Download the Product Application Form (.xlsx) at the bottom of this page.
  4. Start a new application in your Manufacturer Account.
    • Once logged in, click the Applications tab on your Dashboard. Click the green Create Application button. This will lead you to the Create New Application window. Enter the required Application Details and Application Contact information. Be sure to select the Hort Family Grouping application type. After creating the application, you will be redirected to the Application Home.
    • Upload ALL required application materials. To upload supporting documentation, click the Documents section in the left-hand navigation menu of Application Home. Within the Documents section, each question requires a specific document to be uploaded. Questions are determined by the selected application type. Files must be individually uploaded in order to save your progress. All “Required Documentation” must be uploaded before you can submit the application. “Optional Documents” are necessary for evaluating products against the Premium classification requirements and certain Primary Use designations. The system will allow you to replace and delete files as necessary before submitting your application. Download a detailed checklist of required documentation for horticultural applications here.
      • Completed product application form (.xlsx)
      • Manufacturer product specification sheet
      • Marketing brochure
      • Tested driver benchtop report
      • Warranty documentation
      • Safety documentation
      • “All-on” photon flux text report
      • Spectral quantum distribution image
      • Photosynthetic photon intensity distribution image
      • LED specification sheet(s)
      • LM-80 report(s), PPF
      • ISTMT report(s)
      • TM-21 report(s), PPF
      • PPF-denominated maintenance conversion(s)
      • LM-80 report(s), far red
      • TM-21 report(s), far red
      • Non-far red flux maintenance conversion(s)
      • LM-84 report, PPF
      • TM-28 report, PPF
      • LM-84 report, far red
      • TM-28 report, far red
      • Driver specification sheet(s)
      • Driver ISTMT report(s)
      • Fan specification sheet(s)
      • Spectral channel test report(s)
      • Important: all supporting documentation must include the specific, relevant model or part number. Documents and files related to the luminaire, (e.g., LM-79, ISTMT) must include the unique model number of the luminaire that is included on the application. Documentation related to the LED package/model/array (e.g., the LM-80 report) must include the part number of the specific LED package/module/array that is named in the application. Please communicate with any independent laboratory the exact luminaire model number that it should include in its test reports. Visit our FAQs page for further clarification regarding test reports.
  5. Digitally sign the Application Agreement and submit the application.
    • Application reviews will not begin until the application is submitted. After uploading documentation, you must click the green Submit Application button in the top right-hand corner of the Documents section. This button will present you with a digital Application Agreement that includes the DLC Self-Certification Statement, Logo Guidelines Compliance Statement, Surveillance Testing Compliance Statement, and Safety Certification Compliance Statement. Full text of the agreement is available here. Sign the agreement to submit your application.

For those applicants who do not have the appropriate level of authority to sign the agreement, it is recommended that the signing authority create a DLC account under your company’s organization and digitally sign off once the application is complete.

Application Forms