Introduction to UL certification
UL is the abbreviation of English Underwriter Laboratories Inc, which is the most authoritative institution in the United States and a large private institution engaged in safety testing and evaluation in the world. This is an independent, non-profit professional organization that conducts experiments for public safety. It uses scientific testing methods to study and determine various materials, devices, products, equipment, buildings and so on. Whether it is harmful to life and property; Determine, compile and publish corresponding standards and materials that will help reduce and prevent the loss of life and property, and conduct fact-finding business at the same time. In a word, it is mainly engaged in product safety certification and commercial safety certification, and its ultimate goal is to obtain goods with a fairly safe level for the market and make contributions to the protection of personal health and property safety. As far as product safety certification is an effective means to eliminate technical barriers to international trade, UL also plays an active role in promoting the development of international trade.
UL was established in 1894. In the initial stage, UL mainly relied on funds provided by the Fire Insurance Department to maintain its operations. It was not until 19 16 that UL was completely self-reliant. After nearly a hundred years of development, UL has become a world-renowned certification body, with a strict organizational management system, standard setting and product certification procedures. UL is managed by a board of directors composed of safety experts, government officials, consumers, education, public utilities, insurance and standards departments, and the president and vice president are responsible for daily work. At present, UL has five laboratories in the United States, headquartered in Northbrook, north of Chicago, and set up corresponding laboratories in Taiwan Province Province and Hongkong.
UL certification tracking test
As an integral part of UL certification, in order to ensure that the products listed and approved by UL continuously meet UL standards and requirements, UL has formulated a "follow-up inspection" system. "Follow-up inspection" means that UL sends field representatives around the world to the production site of local factories to conduct follow-up inspection on UL products. Its purpose is to ensure that the manufacturer's production process, inspection process and products always meet UL requirements by checking the production process, inspection process and products of the factory against UL standards and subsequent inspection rules.
Basis for follow-up inspection
In order to ensure the implementation of UL's "Follow-up Inspection" system, UL signed a "Follow-up Inspection Agreement" with the manufacturer. According to the "Follow-up Inspection Agreement", the site representative will inspect the factory regularly without prior notice, and the factory shall not refuse the inspection of the site representative without reason.
After the site representative arrives at the factory, he will conduct inspection mainly according to the "Detailed Rules for Follow-up Inspection". Detailed Rules for Follow-up Inspection shall be compiled by UL Engineering Department after testing the samples submitted for inspection. This document includes a comprehensive description of the product, as well as photos and descriptions. It also stipulates various tests that manufacturers often have to do in the production process. Some tests require 100% products, such as stress testing. Part of the inspection can be carried out by sampling, and at the same time, it also stipulates the inspection items that must be randomly selected by the on-site representative during the on-site inspection in the factory. On-site representatives judge whether the test results are qualified according to the detailed information and regulations of these tests.
Track and check the classification of products.
UL's follow-up tests are divided into class r and class l. Class L services are mainly used for products related to life safety, such as fire extinguishers, smoke detectors, fire doors and some products with considerable output, such as power equipment, wires and circuit breakers. For L-class products, manufacturers must order labels directly from UL and attach them to the products. Class R services are mainly used for electrical equipment, such as electric fans, televisions, hair dryers, ovens and other products usually produced by corresponding assembly lines.
UL certified factory audit
Before the first batch of UL certified products are shipped, the local provincial China Import and Export Commodity Inspection Bureau (CCIB) authorized by UL will send people to the factory for inspection. Follow-up inspection is also needed every year.
UL certification inspection rules
The inspection by UL inspector is basically a mechanical operation. According to different products, the inspector's inspection basis includes announcement, procedures, fuui (if any, included in the detailed rules) and UL standard (if required in fuui).
If the factory is producing UL products or UL products in stock when the inspector visits the factory, the inspector will take samples in one of the following ways:
1. Extract all parts from the production line, and then extract a complete product from the warehouse.
2. Extract all parts from the warehouse and add complete products to the production line.
3. Extract complete products from the warehouse for segmentation.
The specific number of samples depends on the detailed rules, FUII (follow-up inspection instructions), SAP (standard attachments) or direct orders from UL Laboratories. Inspectors may not always check all products, but they will try to check all product categories or models within one year or at least two years.
Generally speaking, UL is not too demanding on the production system of the factory. It is only required to measure instruments and equipment once a year, keep the factory's own inspection records, and have certain control measures for unqualified products.
During the inspection, the on-site representatives (UL inspectors) will mainly pay attention to the product itself, and they will inspect the structure, components and assembly of the product one by one according to the above inspection basis. For parts and components related to product safety, the general rules will indicate that they are required to be UL certified products, and will indicate the manufacturer and model; Generally speaking, for injection-molded parts such as shells and shields, the detailed rules will specify their raw materials and size requirements. The site representative will check the above items and UL marks specified in the detailed rules.
In addition, if the detailed rules or standards require on-site testing of products, the on-site representative will ask the factory inspector to do the corresponding testing, and the on-site representative will be present as a witness. If the detailed rules also require samples to be sent to UL for subsequent testing, the factory shall cooperate with inspectors to make corresponding samples. After the inspectors write the sample labels, provide the addresses and seal the samples, the factory will send the samples to the corresponding UL laboratories.
If the products produced by the factory fully meet the requirements of the corresponding inspection standards of UL, and there is no other violation of the tracking service agreement, the inspector will issue a tracking inspection report; The factory representative shall sign the report after confirming its accuracy; One inspection is completed. If there is something inconsistent with the inspection standards in the inspection process, the inspector will issue a Change Notice according to the specific situation and take corresponding measures.
If the UL mark is used for unauthorized products, the inspector will ask to delete the UL mark; For products that do not meet UL requirements, the inspector will remove the UL mark or rework it in the required factory to make it meet the requirements; If the factory disagrees with the above treatment, it can temporarily keep the UL mark, but the shipment must be stopped, and the inspector will inform the corresponding laboratory, and UL will reply to decide whether to keep the UL mark; If it is only a small problem that does not affect product safety, the inspector will make a temporary acceptance decision and report it to the corresponding laboratory; If there are some obvious standard errors, such as typing errors or unit errors, it will not affect the qualification of the ex-factory products, but as a document processing of UL, the inspector will also issue a change notice. Under normal circumstances, unless it is UL's responsibility, the inspector will ask the factory to explain the nonconformities to the corresponding laboratories, and UL will give the corresponding answers according to your explanation.
Of course, the inspector's judgment is only temporary, and the final decision is of course in UL Laboratory. If the factory has any objection to the inspection practice, it can completely reflect it to the corresponding laboratory. At this point, the inspector is obliged to provide the corresponding contact person and contact information. After confirming that the contents recorded in the change notice are correct, the factory representative shall sign the notice.
UL certification service project
UL's product certification and testing services can be divided into listing, approval and grading.
1) list: Generally speaking, the list is only applicable to complete sets of products and various devices and equipment replaced or installed by qualified personnel on site. Products listed by UL include: household appliances, medical equipment, computers, commercial equipment and various electrical products that play a role in buildings, such as power distribution systems, fuses, wires, switches and other electrical components. UL listed products can usually be marked with UL listing logo on each product. Usage of column name symbol.
2) Accreditation: Accreditation service is an item in UL service, and its certified products can only be used as components and raw materials for UL listing, classification or other accredited products. The approved product structure is incomplete, or there are certain restrictions on its use, which cannot guarantee the expected safety performance. In most cases, the tracking service of approved products belongs to category R. Approved products belonging to L category include electronic wire (AVLV2), processing wire (ZKLU2), wire harness (ZPFW2), aluminum wire (DVVR2) and flexible metal tube (DXUZ2). Approved products need approval marks.
3) Classification: The classification service only evaluates the specific hazards of products, or evaluates products that implement standards other than UL standards (including internationally recognized standards, such as IEC and ISO standards). Generally speaking, most classified products are not products used by consumers, but products used by industry or commerce. The classification mark in UL trademark indicates that the product has certain restrictions and prescribed scope when it is recognized by UL. For example, for chemicals such as solvents used in industry, only the range where fires may occur when they reach the ignition temperature is evaluated. The grading service of some products is the same as the listing service, but generally only one or several aspects of the products are evaluated. For example, in the United States, medical X-ray diagnostic equipment must comply with American laws and regulations on radiation emission and beam accuracy, but because UL only regards X-rays as classified products, it only evaluates its non-radiation properties such as mechanical properties and electrical properties.
4) Multi-listing, Multi-accreditation or Multi-grading services: UL applicants can apply for multi-listing, Multi-accreditation or Multi-grading services if their products need to be produced in the name of other companies due to sales needs. In this case, listed, certified or graded manufacturers are allowed to use the name of another company in the product catalog, but the product is not a company code, product code or UL.
5) "AL" listing, accreditation or rating service: If the UL applicant does not want to obtain listing, accreditation or rating service in the name of his own company, he can apply for listing, accreditation or rating service in the name of another company (usually a retailer or wholesaler), that is, "Al" listing, accreditation or rating service. Different from multiple listing, multiple accreditation or multi-level services, the applicant is not a listed person.
6) System certification service: As a member of the International Accreditation Committee, UL has extensively participated in ISO9000 quality system certification, ISO 14000 environmental protection certification, QS9000 automobile industry quality system certification and AS9000 aircraft industry quality system certification service. Up to now, 1 16 factories in China have obtained the UL system certification; Where 2 1 is ISO900 1 certified, 85 is ISO9002 certified, 1 is ISO 1400 1 certified, and 9 is QS9000 certified.
7) Other services of 7)UL: such as certification service, inspection service, fact judgment service and investigation service. I won't introduce it here.
UL certification process
The product application of UL trademark includes five steps:
1. The applicant submits relevant company and product information.
Written application: You should ask UL Company to conduct a written test on your product.
Company information: Provide detailed and accurate Chinese and English names, addresses, contacts, postal codes, telephone numbers and fax numbers of the following units.
(a) Applicant company: the company that applies for product testing and is responsible for all engineering service fees.
(b) Listed companies: companies whose names are listed in various product catalogues published by UL Company.
(c) Manufacturers: manufacturers and producers of products.
Product information: Product information should be provided in English. First of all, to determine whether your product is within the scope of UL testing, you can consult UL's offices in Guangzhou and Shanghai.
(a) Product name: Provide the full name of the product.
(b) Product model: list all product models, varieties or classification numbers that need to be tested in detail.
(c) The intended use of the product: for example, home, office, factory, coal mine, ship, etc.
(d) Parts list: A detailed list of parts and models (classification number), grades and manufacturers' names of products. For insulation materials, please provide the name of raw materials, for example: GE polycarbonate, Lexan type 104. When the parts are certified or recognized by UL, please prove the specific model of the parts and indicate the UL document number.
(e) Electrical performance: electronic and electrical products. Provide electrical schematic diagram (circuit diagram) and electrical performance table.
(f) Structural drawing: For most products, it is necessary to provide structural drawing or explosion drawing, composition table, etc.
(g) Product photos, instructions for use, safety and other items or installation instructions.
2. People make decisions according to the provided product information.
When the product information is complete, UL engineers will make the following decisions based on this information: UL standard on which the experiment is based, engineering cost of the test, test time, number of samples, etc. , and notify you in writing, and send the formal application form and tracking service agreement to your company. The application form indicates the cost limit, which is the highest project cost estimated by UL according to the test project. This fee limit shall not be exceeded without the written authorization of your company.
3. Apply for company remittance and send back the application form and samples.
The applicant signs the application form and the tracking service agreement, and sends the form back to UL. At the same time, samples are sent by bank remittance, post office or express mail. Please give an appropriate description (such as name and model) of the samples submitted for inspection. Please send the application form and samples separately. For each application project, UL will assign a unique project number (Project No), and indicate the project number and the name of the application company when remitting money, sending samples and application forms, which is convenient for UL to check.
4. Product testing
After receiving the application form, remittance and experimental samples signed by your company, UL will inform you of the completion time of the experimental plan. Product testing is generally carried out in UL laboratory in the United States, and UL can also accept the audit data of third-party testing. The experimental samples will be returned or destroyed according to your requirements.
If the product test results meet the requirements of UL standards, UL will issue qualified test reports and follow-up service procedures. The test report will detail the test situation, the indicators achieved by the sample, the product structure and the safety signs applicable to the product. Product description and UL regional inspector's instructions are included in the detailed rules of tracking service. A copy of the test report will be sent to the applicant company, and a copy of the tracking service details will be sent to each production plant.
5. the applicant is authorized to use the UL trademark.
The UL regional inspector in China will contact the production factory for the first factory inspection (initial production inspection). IPI)。 The inspector will check the storage of your products and their parts in the production line and warehouse to confirm whether the product structure and parts meet the detailed rules of tracking service. If required by the detailed rules, the regional inspector will also conduct witness experiments. When the inspection results meet the requirements, the applicant will be authorized to use the UL mark.
After IPI, inspectors will go to the factory from time to time to check the product structure and witness the experiment. The inspection frequency is determined by the product type and output. Most types of products are tested at least four times a year. The inspector's inspection is to ensure that the products continue to meet the requirements of UL. Please inform UL before you plan to change the product structure or components. There is no need to repeat any experiment for minor changes. UL can quickly modify the tracking service rules so that inspectors can accept such changes. When UL thinks that the change of the product affects its safety performance, it needs to apply for the company to resubmit the sample for necessary testing.
The cost of follow-up service is not included in the test fee, and UL will send you another invoice for follow-up inspection service.
If the product test results cannot meet the requirements of UL standard, UL will inform the applicant and explain the existing problems. After improving the product design, the applicant can resubmit the product. You should tell the UL engineer what improvements have been made to the product so that he can decide that the above steps are the steps to apply for UL certification.
UL certification terminology
AL list (multiple column names or approvals)
agent
Appellation procedure (appeal procedure)
Appendix (attached page)
Applicant (applicant)
Authorization page (authorization page)
Category control number (category control number)
Component (component)
Acceptable conditions (applicable conditions)
Control number (control number)
Factory identification (factory identification)
Factory inspection (factory inspection)
"AL" list, classification or identification (multi-column name or identification)
Listing or recognized services established in a name different from that of the applicant (listed person) and authorized by the applicant.
agent
An individual or enterprise entrusted by the applicant to engage in activities related to UL in the name of the applicant.
Appellation procedure (appeal procedure)
If customers have different opinions on the results of engineering tests or follow-up inspections, they can discuss with relevant engineers or field representatives without worrying about endangering future conclusions. If you can't get a satisfactory answer at this level, the customer can appeal to a higher level until the president.
Appendix (attached page)
Part of the detailed rules, including the responsibilities of factory and field representatives and the requirements of related tests. It can also describe the testing of samples sent to UL.
Applicant (applicant)
Enterprises or individuals who apply to UL for testing their components, products or systems. Legally, this party will be responsible for the cost of testing and tracking services, and has the right to obtain all information related to the test results. See also proxy.
Authorization page (authorization page)
Record the inspection rules on the first page of the tracking service factory to authorize the corresponding tracking inspection service (class L or R) and the allowed certification mark.
Class control number (CCN)
Character representation of different product categories in UL listing, identification and classification service. For example, AVLV2 stands for electronic circuit; QOWZ stands for portable lamp. Generally speaking, XXXX is a listed product, XXXX2 is an approved product, XXXX7 is a listed product that meets Canadian standards, and XXXX8 is an approved product that meets Canadian standards.
Component (component)
A certain part of a product, besides participating in the test of the whole product as a part of the whole product, needs to test its performance and/or structure separately. Components can be listed, approved or unlisted.
Acceptable conditions (applicable conditions)
These items are listed in the report of approved or unlisted parts, but they are not used as the inspection basis for field representatives. According to the test results, these items represent the restrictions and conditions when the parts are used in the complete product. For example, in the report of a switch, it may be indicated in the "applicable conditions" that the product is only applicable to the current below 1A or the temperature below 125C.
Control number (control number)
One of the four possible components of the UL certification mark designated by UL. According to different product categories and different tracking services, the control number may change periodically.
Factory identification (factory identification)
An identification mark used by manufacturers who produce the same product in different factories to distinguish which factory the product was produced in.
Factory inspection (factory inspection)
Materials to be submitted for UL certification
The product application of UL trademark includes five steps:
1. The applicant submits relevant company and product information.
Written application: You should ask UL Company to conduct a written test on your product.
Company information: Provide detailed and accurate Chinese and English names, addresses, contacts, postal codes, telephone numbers and fax numbers of the following units.
(a) Applicant company: the company that applies for product testing and is responsible for all engineering service fees.
(b) Listed companies: companies whose names are listed in various product catalogues published by UL Company.
(c) Manufacturers: manufacturers and producers of products.
Product information: Product information should be provided in English. First of all, to determine whether your product is within the scope of UL testing, you can consult UL's offices in Guangzhou and Shanghai.
(a) Product name: Provide the full name of the product.
(b) Product model: list all product models, varieties or classification numbers that need to be tested in detail.
(c) The intended use of the product: for example, home, office, factory, coal mine, ship, etc.
(d) Parts list: A detailed list of parts and models (classification number), grades and manufacturers' names of products. For insulation materials, please provide the name of raw materials, for example: GE polycarbonate, Lexan type 104. When the parts are certified or recognized by UL, please prove the specific model of the parts and indicate the UL document number.
(e) Electrical performance: electronic and electrical products. Provide electrical schematic diagram (circuit diagram) and electrical performance table.
(f) Structural drawing: For most products, it is necessary to provide structural drawing or explosion drawing, composition table, etc.
(g) Product photos, instructions for use, safety and other items or installation instructions.