Gaskets and Seals Program
The basic standard that covers the test methods used to investigate elastomeric gaskets and seals is ANSI/UL 157, "Gaskets and Seals." In addition to evaluating these products for certain common physical properties, UL evaluates these products for specific end-use applications, such as enclosures for electrical equipment, motor fuel dispensing devices, etc., where the governing standard has requirements that differ from ANSI/UL 157.
Gaskets and seals are covered under the following categories at UL based on the type of product and end-use application. A brief description of each category follows.
Category Code Number (CCN)
Gaskets & Seals
Composite Gasket Materials
Gaskets & Seals (JMLU2)
This main gasket and seal category covers elastomeric and composite gasket materials in various forms such as O-rings, seals, shaft seals, flexible cellular gaskets, facings, sheet material, special forms and poured-in-place gaskets investigated with respect to properties such as tensile strength, elongation, compression set, tensile set, hardness, low temperature, and the retention of these properties after accelerated aging and exposure to various environments. This category is designed to provide a profile of the material properties. The material properties help product designers and engineers find materials that meet their requirements and comply with safety standards associated with their products. These materials may additionally be evaluated to specific end-product standard requirements as requested. The material's profile properties and additional end-use applications are published on UL's Online Certification Directory. Gasket and seal manufacturers are encouraged to submit their products to UL for Recognition in this category (JMLU2) to provide broader certification coverage and to make their product's material properties more directly available to customers.
Gasket Materials (JMST2)
This category covers elastomeric materials supplied in sheet form, or as formed or cut gaskets. These gaskets are evaluated for use in specific end-product applications.
Seal Rings (JOHX2)
This category covers "O" rings, shaft seals, and other types of seals and special forms. These seals are evaluated for use in specific end-product applications.
Composite Gasket Materials (JMST)
This category covers composite gasket materials made from natural materials such as cork, plant fibers, or other fibrous materials, and a binder. These gaskets may be supplied in sheets and formed or cut gaskets. They are intended primarily for sealing finished bolted joints of assemblies handling specific flammable and combustible liquids and gases.
To submit a gasket or seal material, please contact Customer Service to request a quote or complete the online Request for Quote form. Customer Service is available globally to help you with the product submittal process or any other inquiries about gaskets and seals. UL recommends completing a submission form when submitting your request.