UL certification for OEMs - what do you need to sell into the US?

How can you sell your electronics products into the North American markets confident they will meet  required regulatory standards and not fall foul of the law?

Quality and safety markings like the European CE mark and the North American UL code are the symbols that tell customers your products have been built to a recognised and uniform standards. 

What is UL certification and what does it mean?

Only those electronic devices or systems that meet required quality standards (such as NEC NFPA 70) can be legally sold and used within the North American market. 

But how do customers and importing authorities know if a specific product actually meets those standards?

Conformity with national safety regulations can be demonstrated by a ‘mark of conformity’ from a qualified, recognised testing laboratory. One of those testing bodies is the organisation known as UL (Underwriter Laboratories).  

The UL was established in 1894 and they are one of the bodies that now oversee the use of product safety markings in the United States and Canada.  The UL defines standards and conducts tests on electrical equipment which incorporate all the relevant national standards.  Only when a company has met these rigorous requirements can they apply the UL marking to their product

What’s the difference between ‘UL listed’ and ‘UL recognised’

These are two UL certification types that you will likely be familiar with - products can be marked as ‘UL listed’ or ‘UL recognised’. 

While they both represent a gold standard for product quality and safety for end users, they are used to certify different product types. 

‘UL Listing’ is for stand-alone products, while ‘UL recognised’ is the marking for components such as fuses, PCBs and cabling that are used to build those end products.

What product types can be UL listed?

There are over 1,500 UL standards including standards covering the following product types:

  • Audio and Video Equipment
  • Information Technology Equipment
  • Medical Equipment
  • Equipment for Laboratory Use
  • Industrial Control panels

“UL listing means that the product has been tested by UL to nationally recognized Safety Standards and has been found to be free from reasonably foreseeable risk of fire, electric shock and related hazards’ in a Division 2 / Zone 2 environment.” 

Source: https://www.ul.com/

What products can be ‘UL recognised’ 

Within those pieces of equipment, the components (such as PCBs) also need to be ‘UL recognised’ - that is built to a particular fire safety and performance standards suitable to their function.  The standards applying to PCBs include UL 94, UL976, UL976F, UL764E  and UL764F.

The UL recognition mark signifies that your board meets the established safety and flammability requirements which is specified for your product type.  Different types of product require boards that are built to different standards that reflect their need for reliability, durability and safety.  Medical devices, for example, will require components that have the very highest performance rating and lowest risk of failure.  To allow for the proper selection of PCBs, therefore, the various standards specify items such as:

  • Flame rating
  • Maximum operating temperature (MOT)
  • Direct support requirements (DSR) compliance
  • Minimum comparative tracking index (CTI) rating

What does a UL mark look like?

Here is an example of a typical 'UL recognition' mark on a PCB.

What does a UL mark look like?

In this case, UL94V-0 signifies that the board meets UL94 flammability requirements at flame class V-0. 

E198312 here is a unique UL Mark identifier for a specific manufacturer, and ML signifies that this is a multi-layer board.

What standards apply to those producing industrial control panels (ICP)?

For those specifying Industrial Control Panels (ICP) for use in the North American market the UL standard 508A applies.  

UL 508A, the Standard for Safety For Industrial Control Equipment, covers industrial control and related devices rated 1500 volts or less that are used for starting, stopping, regulating, controlling, or protecting electric motors.

What’s required by the UL 508A standard?

UL508A defines how ICPs must be designed and manufactured to meet relevant safety standards and regulations in the US, including the National Electric Code (NEC NFPA 70). It covers your use of:

  • Components: When used in the panel design compontents must be from “listed” or “recognized” sources that are certified.
  • Labeling and identification: Conductors and components must be labeled for easy identification.
  • Circuit protection: The design must have built into it the required circuit protection to prevent the electric shock danger to the user or the panel.
  • Spacing: The panel must be designed with the required electrical spacing between components
  • Regional electrical codes: The panel must be designed with full compliance to these codes

Companies specifying control panels for machinery in the US market can use suitably qualified third parties to certify their ICPs to the UL 508A standard.  These third parties gain this certification through undertaking UL’s Industrial Certification panel shop programme.  

What is the Industrial Control Panel Shop Programme?

This training programme run by UL permits CMs and others to apply UL listing marks to the panels they are producing:

“Our Industrial Control Panel Shop Program (ICP Program) allows control panel manufacturers who custom-build or mass-produce ICPs to apply the UL Marks for the U.S. and Canada at their factories. Our ICP program makes it convenient to receive a UL certification while allowing maximum flexibility in panel design. When regulators, specifiers and end-product certifiers see the familiar UL Mark, they can be confident that the panel has met the certification requirements.” 

Source: ul.com

Once certified these third parties are assessed every year to ensure their end products are still meeting the required standards.

The ability to UL list and label your design without going through the UL itself will be important to make the process as seamless and cost effective as possible.

The right CM will  not only ensure that your product is designed and built to meet required standards, but also that you have all the required documentation necessary for it to be audited by regulators and other authorities.

Why is UL certification so important for electronics manufacturers looking to break the US market?

The North American market is a huge commercial opportunity for UK electronics manufacturers, and in the wake of Brexit is becoming a focus of increasing interest for their new business strategies.  

But the North American regulatory environment is quite different from that of the UK and Europe. Figuring out what standards and certification you require often needs expert support. 

There is a lot to learn for OEMs wanting to build products for export to these territories and even more at stake.

Get it wrong and you might end up wasting time, effort and money on unnecessary badging. Or worse, you could end up with your products being impounded because your product has failed documentation checks en route to its destination.

In the UK, OEMs planning to sell their products to the US should look to expert Contract Manufacturers, capable of supplying suitably listed/recognised products and components as required. You should ensure they are qualified to supply the insight, certification and documentation necessary so that your plans to sell your products into these markets can go without a hitch.

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Written by Neil Sharp

Neil has over 25 years’ experience in Electronics Manufacturing Services and Component Distribution. During his career, Neil has held a range of leadership positions in sales, marketing, and customer service. Neil is currently part of the ESCATEC Senior Management Team and is responsible for setting and delivering the overall Group Marketing strategy. Neil heads up the marketing department and is responsible for both the strategy and the implementation of innovative marketing campaigns designed to deliver high quality content to those seeking outsourcing solutions.