UL is the abbreviation of Underwriter Laboratories Inc. UL Safety Testing Institute is the most authoritative institution in the United States, and also a large non-governmental institution engaged in safety testing and identification in the world. It is an independent, non-profit, professional organization that conducts 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 extent of harm; Determine, prepare and issue corresponding standards and materials that can help reduce and prevent loss of life and property, and conduct fact finding business.

Introduction to UL Mark

UL logo style

The 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 part of these marks is UL's pictorial symbols, which are UL's registered trademarks.

Requirements for the use of UL signs

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

2. When the excircle diameter of UL mark is less than 3/8 inch, the registered trademark symbol can be ignored if it is not legible under naked vision.

3. The marks can be directly fixed on the unchanged products by stamping, molding, ink printing, screen printing or similar methods.

4. Acquisition of logo: The manufacturer can reprint or obtain it from UL authorized dealers.

5. ULus sign (only us, no c): safety sign for products entering the US market; CUL (only c, no us): safety sign for products entering the Canadian market; CULus mark: safety mark for products entering the US market and Canada market

Service Items

UL's product certification and test services can be classified into listing, approval and grading.

1. Column name (LIST):

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

2. Recognized:

The recognized service is an item of UL service, and the products identified can only be used as components and raw materials on UL listed, graded or other recognized products. The approved products are not complete in structure, or have certain restrictions on use to ensure 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), processed wire (ZKLU2), wire harness (ZPFW2), aluminum wire (DVVR2), and metal flexible tube (DXUZ2). Approved products are required to have approval marks.

3. Classification:

Grading service only evaluates the specific hazards of products, or the products that implement other standards (including internationally recognized standards, such as IEC and ISO standards) other than UL standards. Generally speaking, most graded products are not products used by consumers, but products used in industry or commerce. The classification mark in the UL mark indicates that there are certain restrictions and specified scope when the product is identified by UL. For example, for chemicals such as solvents used in industry, only the range of fire that 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 evaluates one or several aspects of the product. For example, in the United States, medical X-ray diagnostic apparatus and other equipment should comply with the laws of the United States and the regulations on radiation emission and beam accuracy. However, because UL only uses X-ray as the grading product, it only evaluates its mechanical performance, electrical performance and other non radiation performance.

4. Multiple listing, multiple recognition or multiple classification services:

When a UL applicant has obtained the above listing, approval or grading 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, multiple approval or multiple grading services. In this case, the manufacturer who has been listed, approved or graded is allowed to use the name of another company in the product directory, except for the company code, The product code or other features that UL considers acceptable must be consistent with the original listed, approved or graded products.

5. "AL" listed, recognized or graded services

If UL applicants do not want to obtain listing, recognition or grading services in the name of their own companies, they can apply for listing, recognition or grading services in the name of another firm (usually a retailer or wholesaler), that is, "AL" listing, recognition or grading services. Its difference from multiple listing, multiple recognition or multiple classification service is that its applicant is not a listed person.

technological process

Product application for UL mark includes the following steps:

1. The applicant submits relevant company and product information

Written application: You should request UL to test your products in writing.

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

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

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

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

Product data: The product data shall be provided in English.

(a) Product name: provide 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) The intended use of the product: for example, home, office, factory, coal mine, ship, etc.

(d). Parts list: list in detail the components, model (classification number), rating and manufacturer's name of the product. For insulating materials, please provide the name of raw materials, such as GE Polycarbonate, Lexan Type 104. When a part has obtained UL certification or approval, please prove the specific model of the part and indicate its 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 required to provide the structure diagram or explosion diagram of the product, and the ingredient list.

(g) Photos, instructions for use, safety and other items or installation instructions of the product.

2. Make a decision based on the product information provided

When the product data are complete, UL's engineers make the following decisions based on the data: UL standards on which the experiment is based, engineering costs for testing, testing 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 testing items. Without your written authorization, the expense limit cannot be exceeded.

3. Remittance and return of application form and samples by the applicant company

The applicant shall sign the application form and the tracking service agreement, and send the form back to UL Company. At the same time, the applicant shall send the samples in the post office or by express mail through bank remittance. Please give an appropriate description (such as name and model) to 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.) to indicate the project number and the name of the application company when remitting, sending samples and application forms, so as to facilitate UL's 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 conducted in UL laboratories in the United States, and UL can also accept the audited third-party test data. 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 the test conformity report and the Follow Up Service Procedure test report, which will detail the test conditions, the indicators reached by the samples, the product structure and the safety signs suitable for the use of the product. The detailed rules of tracking service include the description of products and 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 factory.

5. The applicant is authorized to use the UL logo

The UL regional inspector in China will contact the production factory for the 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 are consistent with the tracking service rules. If required in the rules, the regional inspector will also conduct witness tests. When the inspection results meet the requirements, the applicant is authorized to use the UL logo.

After IPI, inspectors will irregularly go to the factory to inspect the product structure and carry out witness tests. The frequency of inspection depends on the product type and production volume. Most types of products will be inspected at least four times a year. The inspector's inspection is to ensure that the products continue to conform to UL requirements. Before you plan to change the product structure or components, please inform UL first. For changes with minor changes, it is not necessary to repeat any experiments, UL can quickly modify the tracking service rules so that inspectors can accept such changes. When UL considers that the product changes affect its safety performance, it needs to apply for the company to resubmit the samples 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 to apply for UL certification.

summary

UL inspectors' inspection is basically mechanical operation. According to different products, the inspector's inspection basis includes Bulletin, Procedure, FUII (if any, included in the 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. Extract each part from the production line plus a complete product from the warehouse.

2. Extract each part from the warehouse and add the complete product on the production line.

3. Extract complete products from the warehouse for splitting.

The specific quantity of sampling depends on the detailed rules, FUII (tracking inspection instructions), SAP (standard attachment page) or the direct order from UL laboratory. Inspectors may not inspect all products every time, 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 on 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 measures for unqualified products.

During inspection, the on-site representative (UL inspector) will focus on the product itself, and they will check the structure, components and assembly of the product 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 shells and shields, the detailed rules will generally specify the raw materials and size requirements. The site representative will check the above items and UL marks specified in the detailed rules.

Field test

In addition, if the detailed rules or FUII or standards require on-site testing of products, the site representative will require the factory inspector to do the corresponding tests, and the site representative will be there to 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 UL's corresponding inspection standards, and there are no other violations of the tracking service agreement, the inspector will issue an inspection report; The factory representative shall sign the report after confirming that the contents are correct; One inspection is completed. In case of any nonconformity 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 using UL mark, the inspector will require to remove the UL mark; If the product does not meet the UL requirements, the inspector will remove the UL mark or rework in the factory to make it meet the requirements; If the factory disagrees with the above handling opinions, it can temporarily retain the UL mark, but the shipment must be stopped. The inspector will inform the corresponding laboratory of the situation, and UL will make a reply to decide whether to retain the UL mark; If there are only some minor problems that do not affect the safety of the product, the inspector will make a temporary acceptance decision 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 eligibility of the factory products, but as a UL document, the inspector will also issue a change notice. In general, unless it is UL's responsibility, the inspector will ask the factory to explain the nonconforming items to the corresponding laboratory, and UL will respond accordingly according to your explanation.

Final decision

Of course, the inspector's judgment is only temporary, and the final decision is of course in UL laboratories. If the factory disagrees with the inspection method, it can fully 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

Certification factory inspection The UL regional inspector in China contacts the production factory for the initial production inspection (IPI). The inspector checks 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 inspector will witness the test. 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 inspection frequency is determined by 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 conform to UL requirements. Before you plan to change the product structure or parts, please inform UL in advance. For minor changes, it is not necessary to repeat any experiments. UL can quickly modify the tracking service rules so that inspectors can accept such changes. When UL considers that the product changes affect its safety performance, it needs to apply for the company to resubmit the samples for necessary testing.

Certification review

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