UL product certification, testing the types of services can be divided into column names, recognition and classification.

1) The column names (LISTED): In general, the listing only applies to complete products, and qualified personnel in the field to replace or install a variety of devices and equipment, UL listing services are a variety of products including: home appliances , medical equipment, computers, business equipment, and the role of the building all types of electrical products, such as power distribution system, fuses, wires, switches and other electrical components and so on. The UL listing of products, usually marked on each product's UL Listing Mark. Listing Mark of usage.

2) recognized (Recognized): UL approved service is a service project, the identification of the product only in the UL Listing, Classification or other approved products as components, raw materials used. Approved products in the structure is not complete, or have certain restrictions on use to ensure the desired security. In most cases, the tracking services are authorized products are R classes. L class is accredited products are electronic line (AVLV2), processing wire (ZKLU2), wiring harness (ZPFW2), aluminum (DVVR2), and metal flexible tube (DXUZ2). Approved product requirements with the approval mark.

3) Classification (Classification): differentiated services only to evaluate the specific hazards of products, or UL standards other than the implementation of standards (including the internationally recognized standards such as IEC and ISO standards, etc.) to evaluate the product. Most consumer grade products are not in general use products, but industrial or commercial use of the product. The Classification Mark UL mark indicates the product identified by the UL have a certain range of restrictions and regulations. For example, a solvent for industrial use such chemicals, to reach its ignition temperature is only possible to evaluate the range of fire. The classification of certain products and services, listing services, the same, but generally only one aspect of a product or a number of aspects of evaluation, such as in the United States, medical X-ray diagnostic apparatus such equipment to the country to comply with U.S. laws and radiated emissions and the provisions of the beam accuracy, but because only the X-ray as a UL rating products, they only evaluate its mechanical properties, electrical properties and other non-radiative properties of these aspects.

4) multiple listing, multiple approval or multi-tiered services: When an applicant in obtaining a UL listing above, approval or grading service, and its products to another company's name to the production to meet the needs of sales, may apply for multiple listing, multiple or multi-tiered services authorized, in which case, get the column name, manufacturer approval or grading is allowed to use the product directory in the name of another company, but the products are the company code , the product code or UL company acceptable to the other features, it must be the original column names, product approval or classification of the same capacity.

5) "AL" listing, approval or classification of service: If UL applicants do not want to get your own column names in the name of the company, approval or classification of service, he can apply with another firm (usually a retailer or wholesaler) in the name of the column name, approval or classification, that is called the "AL" listing, approval or grading service. With the multiple listing, multiple or multi-tiered services recognized the difference between the applicant is not out of their celebrity.

6) System Certification Services: As a member of the International Accreditation Board, UL widely involved in ISO9000 quality system certification, ISO14000 environmental certification, QS9000 quality system certification and the automotive industry AS9000 quality system certification services to the aircraft industry. So far, a total of 116 factories in the country to obtain UL certification system; where ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bi