UL

1. Certification Overview

UL stands for Underwriters Laboratories Inc. It is a leading US safety testing organization and one of the world's largest independent bodies engaged in safety testing and assessment. UL certification is voluntary in the US and primarily covers product safety testing and certification. Product safety is a major concern throughout the US market. More than 40,000 federal, state, county and municipal jurisdictions recognize the UL mark, and Amazon US also requires UL certification for certain products.

 

2. Certification Mark

UL marks are divided into three categories according to the service: UL Listed, UL Classified and UL Recognized Component. UL services cover both US UL standards and Canadian standards (cUL). Marks therefore indicate compliance for the US, Canada or both. The “us” at the lower right indicates US applicability, the “c” at the lower left indicates Canada, and both symbols indicate applicability in both countries.

 

3. Certification Standards

Product		Safety Standards
Power Supplies	ITE / AV Power Supplies	UL 62368-1
	Lighting Power Supplies	UL 8750
	Appliance Power Supplies	UL 1310 UL 1012
	Medical Power Supplies	UL 60601-1
	Industrial Power Supplies (Electronic Transformers)	UL 1310 UL 1012 UL 61010-1 UL 61010-2-201
Terminal Devices	Information Technology (ITE) / Audio-Video (AV) Products	UL 62368-1
	Lighting Products	UL 153 UL 1598 UL 8750 UL 1786 UL 1573 UL 588 UL 2108 UL 924
	Household Appliances	UL 1007 UL 1005 UL 1028 UL 1083 UL 982 UL 1026
	Medical Products	UL 60601-1
	Industrial Products (Transformers)	UL 1310 UL 1012 UL 506 UL 1561 UL 1562 UL 1585 UL 1876 UL 1411 UL 397 UL 697
	Power Tools	UL 60745-1
Batteries	Consumer Batteries	UL 1642 UL 2054 UL 2056
	Traction Batteries	UL 2271 UL 2580 UL 1973 UL 2743
Electric Vehicles	Electric Bicycles and Personal Electric Vehicles	UL 2849 UL 2272

 

4. Test Items

1. Input Testing

2. Temperature Rise Testing

3. Impact / Drop Testing

4. Glow-Wire / Needle Flame Testing

5. Ball Pressure Testing

6. Limited Power Source (LPS) Testing

7. Touch Current Testing

8. Grounding Impedance Testing

9. Constant Temperature and Humidity Testing

10. Vibration Testing and More

 

5. Required Documents

1. Critical Component List (CDF)

2. Schematic Diagram

3.PCB Layout

4. Label / Nameplate

5. Transformer and Inductor Specifications

6. Model List / Differences Table

7. Product Operating or Installation Instructions

 

6. Certification Process

1. Quotation;

2. Arrange payment;

3. Provide the application form, documents and test samples;

4. Perform testing and confirm the report;

5. After approval, obtain the NOA or NOC;

6. An NOA permits shipment with the UL mark. An NOC requires completion of the initial factory inspection before shipment with the UL mark.

 

7. Certification Timeline & Validity

UL certification normally takes 3–4 weeks. Expedited service is available for an additional fee.

 

8. Factory Inspection

UL factory inspections take place four times a year. In addition to quarterly inspections, an annual inspection is also required.

Documents Required for UL Factory Inspections:

1. Production and Quality Control Procedures

2. Inspection Standards for Critical Components and Finished Products

3. Critical Component Certificate (Yellow Card) Records

4. Product Bill of Materials

5. Key Documents for Plastic Material Control

6. Key Documents for Production Control

7. UL Label Records

8. Collection of Bulk Labels from Critical Component Packaging