GLOSSARY



UL symbol

The UL mark is an internationally recognized certification mark for product safety in the North American market. It is issued by UL Solutions and confirms that a product has been tested and certified in accordance with the applicable safety standards.

By displaying a valid UL mark, the manufacturer demonstrates that its product meets the requirements of the underlying certification. Regular inspections conducted as part of the certification program are designed to ensure that production continues to comply with the certified specifications.

However, not all UL marks are the same: There are different UL marks that vary in terms of their scope, type of certification, and underlying safety requirements. It is particularly important for the U.S. and Canadian markets to be familiar with the respective UL symbols and their meanings.

What UL marks and symbols are there?

In the field of UL certification, there are various certification marks that are particularly important for control panel manufacturing and electrical safety in North America. The respective UL symbols indicate the market for which a product has been certified and the type of certification it holds.

For the Canadian market, the UL mark is typically indicated by an additional “C.” The “US” marking indicates certification in accordance with the requirements applicable in the United States. Products certified for both markets bear a combined “C”/“US” marking.

The following section presents the most important UL marks and their significance for the North American market.

UL Listed

The UL Listed symbol is one of the best-known certification marks for product safety in North America. It confirms that UL has tested representative product samples and determined that they comply with applicable safety standards. Regular inspections are conducted to ensure that ongoing production also meets the certification requirements.

The UL Listed mark can be found on numerous products, including electrical appliances, computers, heaters, fuses, smoke detectors, and fire extinguishers. It serves as important evidence of compliance with relevant safety requirements in the North American market.

UL Recognized

The UL Recognized Component symbol identifies components intended for installation in larger products or systems. Unlike the UL Listed mark, it is usually not visible to end users.

This marking can be found, for example, on switches, power supplies, printed circuit boards, and industrial control components. Since these components are not considered standalone end products, their use is subject to specific installation requirements and restrictions that must be taken into account when integrating them into the overall system.

UL Classified

The UL Classified mark identifies products that have been tested and evaluated by UL with regard to specific characteristics, safety risks, or conditions of use. This certification applies exclusively to the specified criteria and does not cover overall product safety.

Typical applications include building materials, fire-rated doors, industrial equipment, firefighting protective gear, and specialty vehicles. The certification mark confirms that the tested properties meet the relevant safety requirements.

UL Functional Safety

The UL Mark for Functional Safety identifies products that, in addition to UL Listed certification, have been evaluated for their functional safety. Functional safety refers to the safety that depends on the reliable operation of safety-critical controls, systems, and software.

The certification mark is awarded in particular to products that perform safety-related functions, such as those found in machinery and industrial equipment. As a result, it is less common than the traditional UL Listed symbol.


Conclusion



The various UL marks indicate different types of certification and safety requirements for products on the North American market. They differ, among other things, in terms of product certification, component recognition, classification of specific characteristics, and functional safety. Understanding the meaning of the UL symbols allows you to better interpret the respective certification and take important requirements into account when using electrical components and control panels.