UL is a shorthand for Underwriter Laboratories Inc. The UL Safety Test Institute is the most authoritative in the United States and is the larger private institution engaged in safety testing and identification in the world. It is an independent, profitable professional agency that conducts tests for public safety. It adopts scientific test methods to study and determine the degree of harm and harm to life and property of various materials, devices, products, equipment, construction, etc.; determine, formulate and issue corresponding standards and help reduce and prevent life-threatening Loss of property information, while conducting fact-finding business. UL certification is a non-mandatory certification in the United States. It is mainly for the inspection and certification of product safety performance. The scope of certification does not include EMC (electromagnetic compatibility) characteristics of the product.

Authentication significance

The meaning of UL certification mark for the company:

1. The entire US market places great emphasis on product safety; consumers and purchasers will choose products with the UL certification mark when they purchase products.

2. The history of UL is more than 100 years old. The image of safety is deeply entrenched in consumers and the government. If you do not directly sell products to consumers, intermediate merchants will also require products to have UL certification marks to make products sell well.

3, US consumers and purchasing units have more confidence in the company's products.

4. The U.S. federal, state, county, and municipal governments have a total of more than 40,000 administrative districts, all of which recognize the UL certification mark.

Authentication step

1. Applicants submit relevant company and product information

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

Company Information: Provide detailed and accurate name, address, contact person, zip code, telephone and fax of the following units in Chinese and English.

(a). Applying for a company: A company that submits a product testing application and is responsible for the cost of all engineering services

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

(c) Production plants: Manufacturers and producers of products.

Product Information: Product data should be provided in English.

(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.

(c). The intended use of the product: for example: homes, offices, factories, coal mines, ships, etc.

(d). Parts List: Details of the parts and models (classification number), rating, and manufacturer's name of the constituent products. For insulating materials, please provide the name of the raw material, for example: GE Polycarbonate, Lexan Type 104. When parts and components have obtained UL certification or approval, please prove the specific model of the part and indicate its UL file number (e). Electrical properties: For electronic and electrical products. Provide electrical schematics (circuit diagrams), electrical performance table.

(f). Structure diagram: For most of the products, structural diagrams or explosion diagrams, ingredient lists, etc. of the product must be provided.

(g). Product photographs, instructions for use, safety, etc. or installation instructions.

2. Make a decision based on the product information provided

When the product data is complete, UL's engineers make the following decisions based on the data: the UL standard on which the experiment is based, the test cost, the time of the test, the number of samples, etc., notify you in writing, and will formally apply and follow the service. The agreement is sent to your company. The fee limit specified in the application form is the largest engineering cost that UL has estimated based on the test item. Without your company's written authorization, this fee limit cannot be exceeded.

3. Apply for company remittance, return application form and sample

UL certification

The applicant signs on the application form and tracking service agreement and sends the form back to UL. At the same time, the bank sends the money and sends the sample at the post office or express mail. Please explain the sample to be sent to the applicant. Name, model). Application forms and samples should be sent separately. For each application, UL will assign a unique project number (Project No.) to indicate the project number and apply for the company name when remittances, samples, and application forms, to facilitate UL inspection.

4. Product testing

After receiving your company's signed application form, remittances, and experimental samples, UL will inform you when the experiment plan is completed. Product testing is generally conducted in UL laboratories in the United States. UL also accepts audited third-party testing data. Experimental samples will be returned or destroyed according to your requirements.

If the product test results meet the requirements of the UL standard, UL will issue a Follow Up Service Procedure test report that details the test conditions, the samples achieved, the product structure, and the safety signs appropriate for use of the product. The tracking service specification includes a description of the product and guidance for UL regional inspectors. A copy of the test report is sent to the applicant company, and a copy of the tracking service details is sent to each production facility.

5. The applicant is authorized to use the UL mark

The UL regional inspector in China contacted the production plant for Initial Production Inspection (IPI). The inspector checked the status of your products and their components in the production line and warehouse to confirm whether the product structure and parts were The follow-up service rules are consistent. If required by the rules, regional inspectors will also conduct eye-catching experiments. When the inspection results meet the requirements, the applicant is authorized to use the UL mark.

Following IPI, the inspector will visit the factory from time to time to inspect the product structure and conduct eye-catching experiments. The frequency of inspections is determined by the type of product and the amount of production. Most types of products are inspected at least four times a year. The inspector's inspection is to Make sure that the product continues to be consistent with UL requirements. Before you plan to change the product structure or components, please notify UL. For minor changes, you do not need to repeat any experiment. UL can quickly modify the tracking service rules so that the inspectors can accept This change. When UL believes that product changes affect its safety performance, it is necessary to request the company to re-submit the samples for necessary testing.

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

If the product test results do not meet the UL standard requirements, UL will notify the applicant to explain the existing problems. After the applicant has improved the product design, the product can be re-inspected. You should tell the UL engineer what improvements the product has made so that it can be decided [ 1] 

IV UL inspection rules, certification review and follow-up inspection UL inspection rules

Inspection by a UL inspector is basically a mechanical job. According to different products, the inspector's inspection basis is based on Bulletin, Procedure, FUII (if any, included in the rules), and UL standards (if FUII is required).

If the inspector visits the factory and the factory is producing UL products or UL products with inventory, 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 plus the complete product on the production line.

3. Extract the complete product from the warehouse for splitting.

The exact amount of sampling depends on the specification, FUII (Tracking Inspection Indication), SAP (Standard Attachment) or direct orders from UL Laboratories. Inspectors do not necessarily test all products for each inspection, but they will try to verify all product categories or models within a year or at least two years.

In general, UL's requirements for factory production systems are not too high. They only require that the instruments and equipment be measured once a year, keep the factory's own inspection records, and have certain control measures for non-conforming products.

During the inspection, the on-site representative (UL inspector) will focus on the product itself, and they will check the structure, parts and assembly of the product on a case-by-case basis. For parts related to product safety, the general rules will specify the requirements for UL certified products, and will specify the manufacturer and model; for shells, shields and other injection molded parts, the general rules will specify the raw materials and size requirements. The on-site representative will check the UL mark specified in the above items and the detailed rules.

testing on the spot

In addition, if the product or the FUII or the standard requires the product to be tested in the field, the on-site representative will ask the factory inspector to do the corresponding tests, and the on-site representative will be witnessed next to it. If the specification also requires sending sample to UL for follow-up testing, the factory shall cooperate with the inspector to make corresponding samples. After the inspector has written the sample tag, provided the address and sealed the sample, the factory sends it to the corresponding UL laboratory.

If the product produced by the factory fully complies with the requirements of UL's corresponding inspection standards and there are no other violations of the follow-up service agreement, the inspector will issue an Inspection Report; the factory representative shall confirm the content of the inspection report after confirming that the content is correct. Signature; a test is completed. If there is any inconsistency with the inspection standard during the inspection process, the inspector will issue a Variation Notice and take corresponding measures according to the specific circumstances.

Remove the UL mark

For UL products using unlicensed products, the inspector will request the removal of the UL mark; for products that do not meet UL requirements, the inspector will request the factory to remove the UL mark or rework to meet the requirements; if the factory disagrees with the above treatment, Temporarily retain the UL mark, but must stop shipping, the inspector will inform the appropriate laboratory, and the UL will reply to decide whether to retain the UL mark; if only a few small problems do not affect the safety of the product, The inspector will make an interim decision and report it to the appropriate laboratory; if there are some obvious standard errors, such as typos or unit errors, it will not affect the eligibility of the factory's products, but as UL's document processing, Inspectors will also issue change notices. Under normal circumstances, unless it is the responsibility of the UL company, the inspector will ask the factory to explain to the corresponding laboratory the non-conforming items, and UL will respond according to your explanation.

The final decision

Of course, the inspector's judgment is only temporary, and the final decision is of course in UL's laboratories. If the factory does not agree with the inspection method, it can fully reflect to the corresponding laboratory. At this time, the inspector is obliged to provide the corresponding contact person and contact method. After confirming that the content recorded in the change notice is correct, the factory representative shall sign the notice.

UL certified factory inspection

The UL regional inspector in China contacted the production plant for Initial Production Inspection (IPI). The inspector checked the status of your products and their parts in the production line and warehouse to confirm whether the product structure and parts were Consistent with the details of the tracking service, regional inspectors will conduct eyewitness tests if required by the rules. When the inspection results meet the requirements, the applicant is authorized to use the UL mark.

Following the IPI, the inspector will visit the factory from time to time to inspect the product structure and conduct eye-catching experiments. The frequency of inspections is determined by the type of product and the amount of production. Most types of products are checked at least four times a year (the cost of tracking services is not included in the test fee).

Certification review

Before the first batch of UL-certified products are shipped, UL-authorized local provincial and provincial-level China Import and Export Commodity Inspection Bureau (CCIC) will send personnel to the factory for review. Annual follow-up inspections.

Introduction to tracking inspection

As an organic part of UL certification, UL has established a "tracking inspection" system in order to ensure that UL's listing and approved products continue to meet UL's standards and requirements. "Tracking Inspection" is to send UL's on-site representatives distributed throughout the world to local factory production sites to conduct UL inspections. Its purpose is to check the production process, inspection process and products of the factory against UL's standards and follow-up inspection rules to ensure that the manufacturer's production process, inspection process and products are always in line with UL's requirements.

Follow-up inspection basis

After the on-site representative arrives at the factory, inspections are mainly conducted in accordance with the "Tracking Inspection Rules." "Tracking Inspection Rules" was compiled by the UL Engineering Department after testing samples submitted. This document includes a comprehensive description of the product, including photographs and manuals. It also stipulates various tests that manufacturing plants often do during production, some of which require 100% of the product, such as pressure tests. Some tests can be carried out by sampling. At the same time, the test items that the on-site representative must check at the factory site inspection are also specified. The on-site representative judges whether the test results are in accordance with the detailed data and regulations of such tests.

Follow-up inspection product classification

The review is divided into first review and quarterly review. The cost of the first review is relatively high. UL's follow-up inspection is divided into R and L categories. The L-services are mainly used for products related to life safety, such as fire extinguishers, smoke detectors, fire doors and some relatively large-volume products such as electrical equipment, wires and circuit breakers. For products belonging to category L, the manufacturer must directly attach the UL ordering label to the product. Class R service is mainly used for electrical equipment, such as fans, televisions, hair dryers, ovens, and other commonly used production lines to produce products.