UL is short for Underwriter Laboratories Inc. UL safety testing institute is the most authoritative organization in the United States, and also a large non-governmental organization engaged in safety testing and identification in the world. It is an independent, non-profit professional organization that does experiments for public safety. It uses scientific testing methods to study and determine whether various materials, devices, products, equipment, buildings, etc. are harmful to life and property and the degree of harm; Determine, compile and issue corresponding standards and materials that can help reduce and prevent the loss of life and property, and carry out fact investigation.

UL introduction

UL is mainly engaged in product safety certification and operating safety certification business. Its ultimate purpose is to obtain commodities with a fairly safe level for the market and make contributions to ensuring 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 a positive role in promoting the development of international trade.

UL was founded in 1894. At the initial stage, UL mainly relied on the funds provided by the fire insurance department to maintain its operations. It was not until 1916 that UL was completely independent. After nearly a century of development, UL has become a world-renowned certification body. It has a complete set of strict organization and management system, standard development and product certification procedures. UL is managed by a Council composed of safety experts, government officials, consumers, education, public utilities, insurance and standards departments, and its daily work is handled by the president and vice president. At present, UL has five laboratories in the United States, headquartered in Northbrook Town, north of Chicago, and has set up corresponding laboratories in Taiwan and Hong Kong. In the United States, UL is the symbol of safety signs for consumers. Globally, UL is one of the most reliable conformity assessment providers for manufacturers.

UL Mark is usually marked on the product and / or product package to indicate that the product has passed UL certification and meets the requirements of safety standards.

form

The most important component of these marks is the UL logo, which is a registered trademark of UL.

UL Mark usage requirements

1. the minimum height of the registered trademark shall be 3/64 inch.

2. when the outer circle diameter of UL Mark is less than 3/8 inch, the registered trademark symbol can be ignored if it is not clearly readable under naked eyes.

3. the mark can be directly fixed on the unchanged product by stamping, molding, ink printing, screen printing or similar methods.

4. acquisition of marks: the manufacturer can reprint or obtain the marks from UL authorized dealers.

5.ulus sign (only us, no c): safety sign for products entering the U.S. market; Cul (only C, no US): safety signs for products entering the Canadian market; CULus mark: safety mark for products entering the American market and the Canadian market

Service items

UL's product certification and testing services can be divided into listing, recognition and classification.

1. listed:

Generally speaking, the listing is only applicable to complete products and various devices and devices that are replaced or installed on site by qualified personnel. Various products belonging to UL listing services include household appliances, medical equipment, computers, commercial equipment and various electrical products that play a role in buildings, such as distribution systems, fuses, wires, switches and other electrical components. Products listed by UL can usually be marked with the UL listing mark on each product. Usage of column name flags.

2. recognized:

Accreditation service is an item of UL service. The products identified can only be used as components and raw materials on UL Listed, graded or other approved products. The approved product is not complete in structure or has certain restrictions in use to ensure the expected safety performance. In most cases, the tracking service of approved products belongs to category R. Approved products belonging to class L include electronic wire (avlv2), processed wire (zklu2), harness (zpfw2), aluminum wire (dvvr2), and metal flexible pipe (dxuz2). Approved products shall be provided with approval marks.

3. classification:

The classification service only evaluates the specific hazards of the product, or evaluates the products that implement other standards other than UL standards (including internationally recognized standards, such as IEC and ISO standards). Generally speaking, most graded products are not products used by consumers, but products used in industry or commerce. The classification mark in UL Mark indicates that the product has certain restrictions and specified range when it is identified by UL. For example, for chemicals such as industrial solvents, only the range of fire that may occur when they reach the ignition temperature is evaluated. The classification service of some products is the same as the listing service, but generally only one or several aspects of the product are evaluated. For example, in the United States, medical X-ray diagnostic equipment and other equipment must comply with American laws and regulations on radiation emission and beam accuracy. However, because UL only regards X-ray as a classified product, it only evaluates its mechanical performance, electrical performance and other non radiation performance.

4. multi listing, multi recognition or multi classification services:

When an UL applicant obtains the above listing, approval or classification services, and its products are to be produced in the name of another company to meet the needs of sales, it can apply for multiple listing, approval or classification services. In this case, the manufacturer who has obtained the listing, approval or classification is allowed to use the name of another company in the product directory, but the product is not the company code, The product code or other features that UL considers acceptable must be consistent with the original listed, approved or classified products.

5. "Al" listing, recognition or classification services

If the UL applicant does not want to obtain listing, recognition or classification services in the name of his own company, he can apply for listing, recognition or classification services in the name of another firm (usually a retailer or wholesaler), i.e. "Al". It differs from multi listing, multi recognition or multi classification services in that the applicant is not a listed person.

6. system certification service:

As a member of the International Accreditation Committee, UL is widely involved in ISO9000 quality system certification, ISO14000 environmental protection certification, QS9000 automobile industry quality system certification and as9000 aircraft industry quality system certification services. A total of 116 factories in China have obtained UL system certification; Among them, 21 are ISO9001 certified, 85 are ISO9002 certified, 1 is ISO14001 certified, and 9 are QS9000 certified.

7. other services of UL:

Such as certification service, inspection service, truth judgment service, research service, etc.

Product application for UL Mark includes the following steps:

1. the applicant submits relevant company and product information

Written application: you should ask UL in writing to test your products.

Company information: provide detailed and accurate name, address, contact person, postal code, telephone and fax of the following units in both Chinese and English.

(a) Applicant company: the company that applies for product testing and is responsible for all engineering service fees

(b) Listed companies: companies listed in various product catalogs published by UL

(c) Production factory: the manufacturer and producer of products.

Product information: product information shall be provided in English.

(a) Product Name: provides the full name of the product.

(b) Product model: list in detail the model, variety or classification number of all products to be tested.

(c) Intended use of the product: for example, home, office, factory, coal mine, ship, etc.

(d) Parts list: list in detail the components, models (classification numbers), rated values and names of manufacturers that make up the product. For insulation material, please provide the name of raw material, e.g. Ge polycarbonate, Lexan type 104. When the parts have obtained UL certification or approval, please prove the specific model of the parts and indicate their UL file number (E) Electrical performance: for electronic and electrical products. Provide electrical schematic diagram (circuit diagram) and electrical performance table.

(f) Structure diagram: for most products, it is necessary to provide the structure diagram or explosion diagram, ingredient list, etc.

(g) Product photos, instructions, safety items or installation instructions, etc.

2. make decisions based on the product information provided

When the product data are complete, UL engineers will make the following decisions based on the data: UL standard on which the experiment is based, engineering cost of the test, test time, sample quantity, etc., notify you in writing, and send the formal application form and tracking service agreement to your company. The expense limit indicated in the application form is the maximum engineering cost estimated by UL according to the test items. Without your written authorization, this expense limit cannot be exceeded.

3. remittance by the applicant company, return the application form and samples

The applicant shall sign the application form and tracking service agreement, and return the form to UL company. At the same time, the samples shall be sent by bank remittance, post office or express mail. Please give appropriate description (such as name and model) to the samples submitted for inspection. Please send the application form and samples separately. For each applied project, UL will specify a unique project number (Project No.) and indicate the project number and the name of the applicant company when remitting, sending samples and application forms, so as to facilitate ul to check and receive.

4. product inspection

After receiving the application form, remittance and experimental samples signed by your company, UL will notify you of the completion time of the experimental plan. Product testing is generally conducted in UL laboratories in the United States, and UL can also accept audited third-party test data. The test samples will be returned or destroyed according to your requirements.

If the product test results meet the requirements of UL standards, UL will issue a test conformity report and follow up service procedure. The test report will detail the test conditions, the indicators reached by the sample, the product structure and the safety signs suitable for the product. The detailed tracking service rules include the description of the product and the instructions for UL regional inspectors. A copy of the test report shall be sent to the applicant company, and a copy of the tracking service rules shall be sent to each production plant.

5. the applicant is authorized to use the UL Mark

UL regional inspectors in China contact the production factory for initial production inspection (IPI). The inspectors check the storage of your products and their parts in the production line and warehouse to confirm whether the product structure and parts are consistent with the tracking service rules. If the rules require, the regional inspectors will also conduct witness tests. When the inspection results meet the requirements, the applicant is authorized to use the UL Mark.

After IPI, inspectors will irregularly go to the factory to inspect the product structure and conduct witness tests. The frequency of inspection depends on the product type and production volume. Most types of products are inspected at least four times a year. The inspectors' inspection is to ensure that the products continue to be consistent with UL requirements. Please notify UL before you plan to change the product structure or components. For minor changes, it is not necessary to repeat any tests, UL can quickly modify the tracking service details so that inspectors can accept such changes. When UL considers that the change of the product affects its safety performance, the applicant company shall resubmit the sample for necessary testing.

The cost of tracking service is not included in the test cost.

If the product test results cannot meet the requirements of UL standards, UL will notify the applicant to explain the existing problems. After the applicant improves the product design, the product can be re submitted for inspection. You should tell UL engineers what improvements have been made to the product so that they can decide that the above steps are the steps for applying for UL certification.

summary

UL inspector's inspection is basically a mechanical operation. According to different products, inspectors' inspection bases include bulletin, procedure, fuii (if any, included in the detailed rules) and UL standard (if required in fuii).

If the factory is producing UL products or has UL products in stock when the inspector visits the factory, the inspector will take samples in one of the following ways:

1. each part from the production line plus a complete product from the warehouse.

2. extract each part from the warehouse plus the complete product on the production line.

3. extract complete products from the warehouse for splitting.

The specific number of samples depends on the detailed rules, fuii (follow-up inspection instructions), sap (standard attached pages) or direct orders from UL laboratories. Inspectors do not necessarily inspect all products for each inspection, but they will try to inspect all product categories or models within one year or at least two years.

Generally speaking, UL does not have too high requirements for the factory production system. It only requires to measure the instruments and equipment once a year, keep the factory's own inspection records, and have certain control means for nonconforming products.

During the inspection, the on-site representative (UL inspector) will mainly focus on the product itself. They will check the product structure, components and assembly item by item 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 the manufacturer and model will be indicated; For injection molded parts such as shell and shield, the detailed rules will generally specify their raw materials and dimensional requirements. The site representative will check the above items and the UL Mark specified in the detailed rules.

Field test

In addition, if the detailed rules or fuii or standards require on-site testing of products, the on-site representative will require the factory inspector to conduct corresponding tests, and the on-site representative will witness. If the detailed rules also require sending samples to UL for tracking test, the factory shall cooperate with the inspector to make corresponding samples. After the inspector writes the sample label, provides the address and seals the samples, the factory will send them to the corresponding UL laboratory.

If the products produced by the factory fully meet the requirements of the corresponding UL inspection standards, and there is no other violation of the tracking service agreement, the inspector will issue an inspection report; The factory representative shall sign the report after confirming that its contents are accurate; One inspection is completed. In case of any inconformity with the inspection standard during the inspection, the inspector will issue a variation notice and take corresponding measures according to the specific situation.

Remove UL marking

For unauthorized products with UL Mark, the inspector will require to remove the UL Mark; For products that do not meet UL requirements, the inspector will require the factory to remove UL marks or rework to make them meet the requirements; If the factory disagrees with the above handling opinions, the UL Mark can be retained temporarily, but the shipment must be stopped. The inspector will notify the corresponding laboratory of the situation, and UL will make a reply to decide whether the UL Mark can be retained; If there are only some small problems that do not affect the safety of the product, the inspector will make a decision of temporary acceptance and report to the corresponding laboratory; If there are some obvious standard errors, such as typing errors or unit errors, it will not affect the conformity of the factory products, but as UL documents, the inspector will also issue a change notice. Generally, unless it is the responsibility of UL company, the inspector will ask the factory to explain the non-conforming items to the corresponding laboratory, and UL will make the corresponding response according to your explanation.

Final decision

Of course, the judgment of the inspector is only temporary, and the final decision is of course in each UL laboratory. If the factory disagrees with the inspection method, it can report to the corresponding laboratory. At this time, the inspector is obliged to provide the corresponding contact person and contact method. After confirming that the contents recorded in the change notice are correct, the factory representative shall sign on the notice.

UL regional inspectors in China contact the production factory for initial production inspection (IPI). The inspectors check the storage of your products and their parts in the production line and warehouse to confirm whether the product structure and parts are consistent with the tracking service rules. If required in the rules, the regional inspectors will conduct witness tests. When the inspection results meet the requirements, the applicant is authorized to use the UL Mark.

Following IPI, inspectors will irregularly go to the factory to inspect the product structure and conduct witness tests. The frequency of inspection depends on the product type and production volume. Most types of products are inspected at least four times a year (the cost of tracking service is not included in the test cost). The inspector's inspection is to ensure that the product continues to comply with UL requirements. Please notify UL in advance before you plan to change the product structure or components. For minor changes, there is no need to repeat any experiment. UL can quickly modify the tracking service rules so that inspectors can accept such changes. When UL considers that the change of the product affects its safety performance, the applicant company shall resubmit the sample for necessary testing.

Certification Review

Before the first shipment of UL certified products, the local provincial China Import and Export Commodity Inspection Bureau (CCIB) authorized by UL shall send personnel to the factory for review. Follow up and check every year.

Follow up inspection

As an integral part of UL certification, UL has developed a "tracking inspection" system to ensure that UL Listed and recognized products continue to comply with UL standards and requirements. "Tracking inspection" means that UL sends field representatives from all over the world to the local factory production site to track and inspect UL's products. Its purpose is to ensure that the manufacturer's production process, inspection process and products always meet UL requirements by checking the factory's production process, inspection process and products against UL standards and tracking inspection rules.

Basis for follow-up inspection

After the site representative arrives at the factory, the inspection shall be carried out mainly according to the "follow-up inspection rules". "Follow up inspection rules" is prepared by UL engineering department after testing the samples submitted for inspection. This document includes a comprehensive description of the product, as well as photos, instructions, etc. It also stipulates various tests that the manufacturing plant should often perform during production, some of which require 100% of the products to be tested, such as voltage withstand test. Some inspections can be carried out by sampling. At the same time, it also specifies the test items that must be spot checked by the on-site representative during the on-site inspection of the factory. The site representative shall judge whether the inspection results are qualified according to the details and regulations of such tests.

Follow up the classification of inspection products

The review is divided into the first review and the quarterly review. The cost of the first review is relatively higher. The follow-up inspection of UL is divided into class R and class L. Class L service is 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 products belonging to class L, the manufacturer must directly order labels from UL and affix them to the products. Class R services are mainly used for electrical equipment, such as fans, televisions, hair dryers, ovens and other products usually produced by corresponding assembly lines.

Technical Term

"Al" listing (multiple column names or approvals)

Agent

Appeals procedure

Appendix (attached pages)

Applicant

Authorization page

Category control number

Component

Condition of acceptability

Control number

Factory identification

Factory inspection

"Al" listing, classification or recognition

Listing or recognition services established in the name of another party different from the applicant (listed person) upon the application and authorization of the applicant

Agent

An individual or enterprise entrusted by the applicant to engage in activities with UL in the name of the applicant

Appeals procedure

If the customer has different opinions on the results of engineering test or follow-up inspection, it can discuss with relevant engineers or Site Representatives without worrying about endangering future conclusions. If a satisfactory response cannot be obtained at this level, the customer can appeal to a higher level until the president.

Appendix (attached pages)

Part of the detailed rules, including the responsibilities of the factory and Site Representatives and the requirements for relevant tests. It may also describe the tests performed on samples sent to UL.

Applicant

An enterprise or individual that applies to UL for testing its components, products or systems. Legally, this party will be responsible for the cost of testing and tracking services, and has the right to all information related to the test results. See also agent.

Authorization page

File on the front page of the factory inspection rules for tracking service to authorize the corresponding tracking inspection service (class L or class R) and the allowed certification marks

Category control number (CCN)

The character representation of different product categories in UL listing, approval and classification services. For example, avlv2 indicates electronic line; Qowz refers to portable lamp. Generally, XXXX is a listed product, xxxx2 is an approved product, xxx77 is a listed product conforming to Canadian standards, and xxx98 is an approved product conforming to Canadian standards.

Component

In addition to participating in the test of the whole product as a part of the complete product, a part of the product also needs to test its performance and / or structure separately. Components can be column, approved, or non column assemblies.

Condition of acceptability

These items are listed in the report of approved or unlisted parts, but are not used as the inspection basis of the site representative. Based on the test results, these items indicate the limitations and conditions when the parts are used with 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 125 ℃.

Control number

One of the four possible components of a UL approved mark, designated by UL. The control number may change periodically according to different product categories and different tracking service categories.

Factory identification

An identification mark used by manufacturers who produce the same product in different factories to distinguish which factory a product is produced in.

Factory inspection

UL certification focuses on industries

Audiovisual equipment

automobile

component

Household appliances

Industrial control equipment

information technology equipment

lamps and lanterns

Medical devices

plastic

Information equipment

Wire and cable

UL serves people by number

UL94 certification - test items

UL94 certification not only evaluates the flame retardancy of plastic materials, but also includes the analysis and testing of thermal and electrical properties of plastics. In addition, the long-term thermal aging performance of plastics under high temperature (air oven thermal aging), water, ultraviolet, cold, etc. are all taken as the final evaluation of materials.

The performance evaluation of materials for UL94 certification includes

94 flammability UL Listed

UL Listed 746a electrical and mechanical properties

UL 746b heat aging procedure

UL 746c audit dossier

Outdoor adaptability of plastics

Component qmqs2

Color qmlj2

Materials used in special environments are those that have certain critical operating and / or environmental conditions after maintaining contact for the performance required in the application of the product used for the particular final investigated material. This will include exposure to different types of ultraviolet (UV) radiation.