4.1 UL certification
UL is Underwriters Laboratories Inc. (Underwriter'Laboratories Inc) acronym, is a non-profit organization established in 1984. The agency obtained a certified electronic products can be freely sold in the US market, without the certification of electronic products in most US states sales will be limited. Since the UL authority, obtain UL certified products are recognized in many countries.
For different types of services UL, UL mark can be divided into three categories, namely, the column name, classification and recognition signs.
1. Listed (Listed). Only for the complete products and a variety of devices to replace or qualified person or device installed on site. Belonging to the UL listing service products include: IT equipment, AV equipment, refrigerators, vacuum cleaners and other electrical equipment. For the final product label UL Listing Mark, we should test the samples by the UL, to confirm that there is no risk of fire and electrical hazards.
2. Recognized (Recognized). Recognized mainly for components and the implementation of a safety certification material. Accredited service recognized by the components that will be assembled in the finished product, components must meet the license conditions related to applied to the corresponding products. Such as: switch, power supply, printed version, transformers, cables, plugs, plastic materials are recognized objects.
3. Classification (Classified). UL classification service, is in accordance with relevant laws, regulations, and other products for commercial or industrial environments are a safety certification program to assess the risk of specific properties and so on. Grading services mainly for building materials and various fire equipment and navigation equipment.
Three markers are used on three different service products, can not be mixed, otherwise it is considered to be counterfeit products. UL's service is not only based on the US UL standards, according to Canadian Standards (cUL). Thus, UL mark is also divided into products for UL and cUL products and meet both three.