Every HVAC business out there wants to make sure that all of the products that they put out in the market are of the best possible quality. After all, they naturally want their customers to have a great experience using their products. The last thing that they want is to receive complaints about how their products malfunction easily or, worse, how their customers got injured while using the products. 

It is important that the products manufactured or sold by HVAC businesses be tested and certified that they are, indeed, high-quality. Luckily, there are a lot of these certification companies out there. But one of the most well-known and well-respected certification companies is arguably the Underwriters Laboratories.

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What Are the Underwriters Laboratories (UL)?  

Generally speaking, the Underwriters Laboratories (UL) a global safety certification company that is headquartered in Northbrook, Illinois. The company aims to create a better world by applying science to solve safety, security, and sustainability challenges. And they plan to achieve this goal by conducting rigorous independent research, analyzing safety data, convening experts worldwide to address risks, sharing knowledge through safety education and public outreach initiatives, and developing standards to guide the safe commercialization of evolving technologies. 

UL was established in 1894, and ever since that year, the company has set up main offices in four countries. They have also served in about 104 countries to date. Additionally, UL is one of several companies that are approved to perform safety testing by the U.S. federal agency Occupational Safety and Health Administration (OSHA). In fact, OSHA has currently maintained a list of approved testing laboratories, which are known as Nationally Recognized Testing Laboratories (NRTLs).

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UL in the U.S. and Canada

It’s true that Underwriters Laboratories serves a number of countries, but in particular, the company is an accredited standards developer in both Canada and the U.S. under the designations ULC Standards and UL standards respectively. What this means is that UL is able to develop standards to advance safety, performance, and sustainability to meet stakeholder needs and bridge standards development gaps across much of North America. 

In the United States, UL Standards is accredited by the American National Standards Institute (ANSI). Meanwhile, in Canada, ULC Standards and UL Standards are each accredited by the Standards Council of Canada (SCC) as a nationally recognized standards development organization (SDO) to develop the National Standards of Canada (NSCs). 

In both countries, UL standards developers represent the very best in scientific methodology and testing expertise combined with invaluable input from experts and stakeholders — from industry to academia, regulatory to retail, manufacturers to end-users — through a recognized, consensus-based standards development process. As a result, this enables regulators, businesses, and consumers to feel confident about the products and services they regulate, use, and purchase. 

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The UL Mark and the cUL Mark

With all of that said, UL makes use of two marks on electrical products to indicate that the products have been designed, built, and tested to be in accordance with safety standards for the U.S. and Canada. And these marks are the UL mark and the cUL mark.

To begin with, the Underwriters Laboratories UL mark applies to products that have been designed and approved for the U.S. market and have received specific Underwriters Laboratories certification that they comply with the respective U.S. standards. These standards are specified in ANSI/NFPA 70, the National Electrical Code and, more specifically, the ANSI/UL 484 standard for special purpose air conditioners. 

Meanwhile, the cUL mark applies to products that are intended for the Canadian market that have been tested and found to comply with the requirements of CAN/CSA 22.1–12, which is the Canadian Electrical Code that is issued by the Canadian Standards Association (CSA). Included in this code under section 22.2 are two sections, numbers 236-M90 and 117 that deal with heating and cooling equipment and special purpose air conditioners. 

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What’s the Difference Between the UL Mark and cUL Mark?

A lot of the times, people use the UL mark and the cUL mark interchangeably even though the fact of the matter is that these two are not necessarily the same. Sure, they both have their own share of similarities, but that said, it is still important to note that there are many differences between the two. An example of their many differences is the fact that Canadian codes reflect a stronger European influence. This can be seen in the frequent reference to IPXX enclosure protection ratings in Canada, although the U.S. NEMA enclosure ratings are also used. 

But in addition to that particular example, the differences between the UL and cUL marks can be seen in the certification processes of both countries. 

The U.S. Safety Certification Process

In the United States, the safe installation of electrical products is assured by conformance to NFPA 70, the National Electrical Code (NEC). Although the NEC itself is not a mandatory standard, it is adopted as law in almost every state or locality in the country. The enforcement of the NEC is delegated to the local Authority Having Jurisdiction (AHJ), such as a building inspector or fire marshal. 

Sections 90.7 and 110.3 of the NEC define the parameters for independent testing labs to judge the suitability of electrical equipment to the appropriate American National Standards for the equipment. There are a few sections of the NEC that require specific types of electrical equipment to be listed, including Section 410.6 which states that all luminaires must be listed. That said, there are no sections of the NEC that require products to be UL listed. 

Several colde experts believe that the NEC intentionally left the definition for “Listed” generic to allow for competition between third-party certification bodies and to prevent monopolization of the product safety certification market. 

Standards Development Organizations and Certification Bodies

Standards Development Organizations (SDOs) create the actual standards that electrical products are tested against to ensure safe operation. The standards are developed by committees whose members may include employees of product manufacturers and testing laboratories. 

In the U.S., the ANSI is the authority for publishing the American National Standards for electrical products. As such, ANSI assigned SDO status to UL to develop these standards. 

Likewise, in Canada, the Standards Council of Canada granted SDO status to CSA Group for the development of the Canadian National Standards. The Canadian National Standards also recognizes UL as an accredited Certification Body that can test and list products to Canadian standards. 

Even though UL and CSA act as both an SDO and third-party Certification Body, there is no requirement for the certification of a product to be performed by the SDO that is responsible for overseeing the development of the standard. Any accredited NRTL can be used by a manufacturer to evaluate their products.

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What Does It Mean If the Product Is UL-/cUL-Certified?

There is a misconception that cUL-certified products are only for use in Canada and cannot be sold or installed in the U.S. while UL-certified products are for the United States and global use. However, this is actually not the case. Depending on the certification, products certified by both marks can be used locally and internationally. 

In truth, product manufacturers are not required to contact the SDO, and many actually don’t. The publishing of standards and the testing of products are two completely different functions. Standards are available to any qualified laboratory selected by a manufacturer to test and certify the product before it goes to market. 

Additionally, all NRTLs use the same testing standards regardless of which lab performed the tests. And as for Underwriters Laboratories, when new products are introduced or it is designed to obtain approval for existing products, the company is able to perform unified testing to verify compliance with the Canadian and U.S. standards. For that reason, a lot of products are both cUL- and UL-certified, or cULus-certified for short. This approach is a cost-effective way of obtaining both UL and cUL approvals. 

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The HVAC industry is one that is predominantly populated by businesses that manufacture and sell electrical products. For that reason, it is incredibly important for HVAC businesses to offer products that are of the best quality. After all, the last thing that they want to happen is to hear about their products malfunctioning or, worse, their customers getting hurt by a defective product. 

For this reason, HVAC businesses must make sure that their products are tested and certified first before they are sold to the general public. Fortunately, there are a lot of companies out there that specialize in testing and certifying products like the HVAC ones. And one of the most well-known and reputable is the Underwriters Laboratories (UL).

UL is a global safety certification company that has been around since 1894, and so, anyone can expect that the company knows everything about testing and certifying electrical products. In fact, they have served companies in over 104 countries, and in 46 of them, UL has set up main offices. Additionally, UL has been recognized by several government agencies, particularly the SDOs in both the U.S. and Canada, as one of the few companies that are approved to perform safety testing. This means that if UL has tested the products, the products can receive both the UL and cUL certifications — or, in other words, the cULus certification. 

Long story short, UL is a well-respected certification company, and earning their approval for your products will add more credibility to your own HVAC business. Because of this, you should definitely consider enlisting UL to test and certify your products. That way, you will know for sure that your products are of high quality and that your customers will be satisfied with the performance of your products. And when that happens, your business is more likely to grow even further. 



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