Consumers trust markings like UL, CSA, and CE on products in order to ensure they are buying products that meet certain safety and/or performance standards. These standards apply to more products than the average person is probably aware of, and similarly manufacturers often have questions about whether or not they need to comply with a standard and which one. They cover a broad range of products and new standards are constantly evolving, so this snippet does not encompass every standard, but it will give an explanation for some commonly seen markings and what questions manufacturers should ask to determine whether or not they should get these markings.
The UL Mark
One of the more familiar marks, the UL Marking, actually has a few variations that appear on both packaging and product, each with its own specific meaning. The only way to determine if a product has been certified by Underwriters Laboratories® is to look for the UL mark. Three common variations [see Fig. 1] are: one used only in the United States, one used only in Canada and one for both the United States and Canada. The C-UL Mark is applied to products for the Canadian market. The products with this type of Mark have been evaluated to Canadian safety requirements, which may be somewhat different from U.S. safety requirements. The optional C-UL-US Mark indicates compliance with both Canadian and U.S. requirements. UL encourages those manufacturers with products certified for both countries to use this combined Mark, but they may continue using separate UL Marks for the United States and Canada.
A UL Listing Mark on a product is always composed of four elements: the "UL in a circle Mark, the word "LISTED in capital letters, an alpha-numeric control number, and the product name, (e.g., "toaster and "portable lamp). Sometimes the UL file number is used as company identification. The UL Listing Mark on a product is the manufacturer's representation that samples of that complete product have been tested by UL to nationally recognized Safety Standards and found to be free from reasonably foreseeable risk of fire, electric shock and related hazards and that the product was manufactured under UL's Follow-Up Services program.
"UL's new holographic label is the most recent element in our efforts to protect and enhance the integrity of our UL Mark," said Brian Monks, UL's vice-president of Anti-Counterfeiting Operations. "The new label technology will further help retailers, customs officials and other law enforcement agencies around the world determine the legitimacy of UL Marked products."
The CSA Mark
For Canada: A CSA mark on its own, without indicators, means that the product is certified primarily for the Canadian market, to the applicable Canadian standards. If a product has features from more than one area, (e.g. electrical equipment with fuel burning features), the mark indicates compliance to all applicable Standards. For Canada and the U.S.: A CSA mark with the indicators "C" and "US" or "NRTL/C" means that the product is certified for both the U.S. and Canadian markets, to the applicable American and Canadian standards. If a product has features from more than one area, (e.g. electrical equipment with fuel burning features), the mark indicates compliance to all applicable Standards.
The CE Mark
The CE Marking on a product is a manufacturer's declaration that the product complies with the essential requirements of the relevant European health, safety and environmental protection legislation, in practice by many of the so-called Product Directives. These directives contain the "essential requirements" and/or "performance levels" and "Harmonized Standards" to which the products must conform. Along with more directives' becoming effective, more and more products are required to bear the CE Marking for gaining access to the EFTA & European Union market. However, many non-EU exporters are still unaware of or unsure about this fact and its impact on their business. Unfortunately, there is no comprehensive list of the products that require a CE marking. Therefore, it is the manufacturer's responsibility to determine if a product requires a CE marking. CE Marking is most probably required if you export to the 27 European Union (EU) and 3 European Free Trade Association (EFTA) member states the following 20 groups of products. A good starting place to check for requirements is http://www.ce-marking.org/what-product.html.
The UL, CSA, and CE mark exist to protect the consumer and ensure product quality and safety. As you can see, which marking you see depends mostly on where the part is manufactured or imported. Some codes, called harmonized codes, are recognized by more than one agency. For further information, please refer to the sources below.