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Architectural Services: FAQ

Where do I find UL rated fire resistive designs, systems, or assemblies?

Answer: Fire resistive designs, systems, or assemblies are found in the UL Fire Resistance Directory or the Online Certifications Directory.

How do I locate an appropriate UL rated fire resistive design, system, or assembly in the UL Fire Resistance Directory?

Answer: The UL Fire Resistance Directory is divided into three volumes:

  • Volume 1 contains results of tests on the basic columns, beams, floor/ceilings, roof/ceilings, and walls. Each construction is identified by an alpha-numeric design number.
  • Volume 2, which is in reality Volumes 2A and 2B, contains the results of tests on electrical circuit protective systems, thermal barrier systems, fire rated grease and ventilation duct assemblies, joint systems, perimeter fire containment systems, and firestop systems. Again, each construction is identified by an alpha-numeric system or assembly number.
  • Volume 3 contains product certifications of dampers, fire doors, fire door frames and glazing materials. Each certification is index under the manufacturer's name within the appropriate product category.

What are the steps involved in using and understanding the UL Fire Resistance Directory?

Answer: When first using the UL Fire Resistance Directory, it is suggested you review the relevant Guide Information. The Guide Information for each product area contains many essential details you need to know to understand what follows. It typically contains:

  1. Information on the equipment, materials or systems included in the product area or category.
  2. Intended use, restrictions or applicable supplemental information.
  3. Standards used to evaluate products under the product area or category.
  4. Information on the UL Listing or Classification Marking that applies to the product area or category.

The Guide Information for the basic columns, beams, floor/ceilings, roof/ceilings, and walls is found near the beginning of Volume 1 of the directory under the heading "Fire Resistance Ratings - ANSI/UL 263 (BXUV)". Included in this Guide Information is a table identifying the significance of the alpha-numeric characters of the design numbering system. For example, this table will identify that U300 series of designs describes wall assemblies constructed of wood studs protected with gypsum board, lath, and/or plaster.

To find a suitable design, you need to understand:

  • What makes up a design
  • Basic information about the particular application
  • The relevant code requirements
  • The numbering system used to identify these designs.

At that point, it is a matter of reviewing the designs within the appropriate series and selecting one most appropriate for your application.

Likewise, Volumes 2A and 2B contains Guide Information for electrical circuit protective systems, thermal barriers, fire rated grease and ventilation ducts, joint systems, perimeter fire containment systems, and firestop systems. These certifications are found under the headings "Electrical Circuit Protective Systems (FHIT)", "Fire Resistive Duct Assemblies (HNKN)", "Thermal Barrier Systems (XCLR)", "Joint Systems (XHBN)", "Perimeter Fire Containment Systems (XHDG)" and "Through-Penetration Firestop Systems (XHEZ)".

How do I locate the appropriate UL rated fire resistance rated design, system or assembly in the UL Online Certifications Directory?

Answer: The UL Online Certifications Directory allows you to search for listings using a variety of methods, such as manufacturers name, model number, UL file number, etc. To use this database simply click on the Certifications link on the left of our web pages, or see http://database.ul.com/. For instructions on the use of this database, click on the Quick Guide at the top of the page or see http://www.ul.com/regulators/quickguide.html

How can I obtain an engineering judgment from UL accepting a modification to an existing UL fire resistance rated design, system, or assembly?

Answer: Any changes to existing designs, systems, and assemblies must be submitted to UL by the sponsor of the design. UL will conduct an engineering study at the request of the design sponsor only. Typically, the design sponsor is the manufacturer of one of the critical design components.

How do I obtain assistance from UL in answering questions regarding the details of a UL design, system or assembly?

Answer: The UL Architectural Services Group offers technical assistance relating to Fire Protection related certifications. Types of assistance includes help in understanding 1) the organization of the Fire Resistance Directory, 2) how to read UL designs, systems or assemblies, 3) the Guide Information and how it relates to the individual designs, systems or assemblies, 4) the use of the Online Certifications Directory, and 5) clarification of the information in the designs, systems or assemblies. Please contact us by emailing your question to NBK.Architectural.Services@US.UL.com or contact us by phone at (847) 272-8800, Extension 40057.

Since UL cannot show preference of one design, system or assembly over another, we are unable to recommend any specific design.

Does UL provide building code interpretations?

Answer: No. The final interpretation of a particular code section is always the decision of the local authority having jurisdiction (AHJ). The AHJ has tremendous responsibility, which is placed on the AHJ by the local and state legislators when the legislature adopts codes specifying that a product or installation is only acceptable when approved. Approved is defined as being acceptable to the AHJ. As such, it is suggested that you contact the code authority having jurisdiction over the project with questions about an interpretation of the code section in question.

The International Code Council (ICC) provides non-binding code interpretations of their codes. More information on these interpretations can be obtained from the ICC website.