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Q&A: UL Critical Component Identification in Fire Resistance-rated Designs

Have you ever wondered why some items within UL Certification designs have asterisks following an item’s description? In this Q&A, we’ll explain what their meaning is.

May 20, 2020


When I look at certain UL Certifications (designs), such as the fire-resistance-rated wall design BXUV.U305, I notice there are certain items that have an asterisks “*” following the item description.  For example, Item 3 shows “Gypsum Board*”.  What does this “*” symbol mean and what is required of me as the user of the Certification?

BXUV.U305 excerpt:

Design No. U305

March 10, 2020

Bearing Wall Rating — 1 Hr

* Indicates such products shall bear the UL or C-UL Certification Mark for jurisdictions employing the UL or C-UL Certification (such as Canada), respectively.

Diagram of a UL Certified Bearing Wall

1. Wood Studs — Nom 2 by 4 in. spaced 16 in. OC max, effectively firestopped.

2. Joints and Nail-Heads — Joints covered with joint compound and paper tape. Joint compound and paper tape may be omitted when square edge boards are used. As an alternate, nom 3/32 in. thick gypsum veneer plaster may be applied to the entire surface of Classified veneer baseboard with the joints reinforced with paper tape. Nailheads exposed or covered with joint compound.

3. Gypsum Board* 5/8 in. thick paper or vinyl surfaced, with beveled, square, or tapered edges, applied either horizontally or vertically. 


Most UL fire resistance-rated certifications (designs) consist of various specified components constructed in a very specific manner and are considered as an complete assembly.  Fire resistance-ratings apply only to assemblies in their entirety and individual components are not assigned a fire resistance-rating.

Each individual item in the assembly must meet required specifications for the assembly to maintain its hourly fire resistance-rating once constructed in accordance with the UL Certification (design).  Depending on the individual UL Certification (design), the discrete component may or may not be required to be a UL Certified product. Those components required to be UL Certified are identified by an “*” symbol in the design specifications.  Also within the UL Certification is a key that defines the meaning of the “*”, which is as follows:

* Indicates such products shall bear the UL or C-UL Certification Mark for jurisdictions employing the UL or C-UL Certification (such as Canada), respectively.”

This means the individual product associated with the “*” must follow UL’s Certification requirements for that particular product category and the product must physically bear UL’s Mark.  If a product intending to be used bears the same name as a product specified in the design, the product must also bear UL’s Mark to be considered as Certified by UL and therefore eligible for use in the assembly. 

If an individual item/product within the design does not have an “*” in the general description, only the specifications identified in the description must be satisfied.  Using the example of a UL design BXUV.U305, Item 1, Wood Studs, does not have a “*” symbol following the item description and therefore the wood studs are not required to be a UL Certified product.  In contrast, Item 3, gypsum board, does have a “*” symbol following description and is required to be a UL Certified product and carry a UL Mark.  In the case where a “*” is next to the item description and a product manufacturer is not identified, any product Certified within the appropriate product category may be used to satisfy the item requirement.  

Such product requirements are detailed within the item description, and also may include the products from individual manufacturers that can satisfy the design requirements.  To deliver the fire-resistance rating of the UL Certification (design), all details specified within must be followed as published in the designs. 

Whether you are an architect, engineer, contractor, code authority or other user of UL Certified fire resistance-rated designs, it is imperative that you verify that all of the items within the UL certification (design) meet the defined criteria.  In particular, confirm all individual items specified with an “*” are UL certified products and bear the UL Mark.