What Does ETL or UL Listed Mean?
When you’re trying to run cables to make a network function, you don’t always have the luxury of thinking about the specific metrics and design elements behind the cables you’re using. You just need to get them from one port to the next, however you can.
The problem is that not all Ethernet cables are equal, and when you run them through walls or attics or other shortcuts, you could unwittingly create a fire risk.
Fortunately, there are groups out there that help you know which cables are safe for these kinds of applications, and two of the most prominent are ETL and UL. A product can be on a pre-approved list with either group, and that’s a good sign that you aren’t about to create a fire.
The ETL List
All the way back in 1896, Thomas Edison’s labs came up with an idea to systematically test electric components and products for safety. The tests were run through Edison’s Electrical Testing Labs (ETL), and the concept persists to this day.
While things have changed over the 100+ years of ETL certification, it’s still a widely recognized stamp of approval that tells you the product you are considering is up to par on safety standards.
These days, ETL approval involves a review of a number of safety standards from recognized bodies. Ultimately, the ETL crew hand-picks their criteria for certification, and any product that gets a stamp of approval was tested in an ETL-certified lab.
For clarity, ETL does not directly run all of the certification labs, but the labs have to go through a certification process before they are approved to perform ETL list testing.
Ultimately, what you’re seeing is that a product on this list has been thoroughly vetted by a long-established, well-respected safety test (or tests).
The UL List
Now that we’ve covered the ETL list, what does it mean to be UL-listed? It’s the same concept, but UL stands for “Underwriters Laboratories” and represents its own standard. You’re still looking at a stamp of approval specifically related to safety in electrical products, but the details are different.
UL sets a unique set of safety standards, and while there are crossover points between the two lists, they are not identical.
It’s worth noting that UL has actually been in this business a little longer, beginning its testing process in 1894.
Regardless, UL is as trusted as ETL. Which one is better is a matter of debate, and when we compare them in a bit, you’ll be able to decide for yourself if you prefer one stamp over the other. What you can trust, though, is that ETL-certified products are up to industry standards for electrical safety.
Why Do These Lists Matter?
In case it wasn’t clear from the previous descriptions, these lists are all about verifying safety standards in products. More importantly, they provide verified third-party testing of products. If you see either seal of approval, you know that you aren’t looking at some random, untested product. The product has been through a level of safety rigor, and that can give you more confidence in the product’s performance.
Specifically, both lists thoroughly test fire safety and flammability in their products. That allows you to use the products as directed with minimal fire danger. That can help with compliance, insurance costs, peace of mind, and anything else you might associate with fire safety.
What Are the Key Differences Between the Lists?
With all of that covered, you might be wondering which list matters more. The short answer is that both lists are widely recognized across the United States and Canada, and either seal of approval denotes quality in terms of fire safety.
That said, there are a few key differences.
The most notable is that ETL does not come up with its own set of safety standards. Instead, they source standards from other authorities on the subject, like the National Electric Code and even the UL. ETL organizes these standards and certifies the labs that perform the tests, but you can see how there are multiple parties involved with the whole thing.
UL keeps things a bit more centralized and under their own control. The UL parameters and tests are determined entirely in-house, and UL runs testing labs directly as well. As a result, some in the industry claim that UL certification is a little harder to gain and as a result, is a little more valuable.
On the other hand, UL testing can be delayed, and it can be more difficult for products to get into a lab for testing in the first place, so you can find product lines that might be up to UL standards but were never tested. Additionally, the complications with UL testing can drive up development costs for manufacturers, so some will stick with ETL to avoid that expense. Others might add a UL markup to their products.
Here’s the bottom line. Both certifications are valuable and well-respected. In many cases, each seal of approval involves the exact same tests. Any preference between the two will lie in the minute differences, not any major gaps from one standard to the other.
How Does It Apply to Ethernet?
Let’s bring all of this home with a specific application. If you’re looking at Ethernet cables, what do those ETL or UL stamps really tell you?
In this case, it’s all about fire safety. An Ethernet cable on either list is appropriately designed and tested to minimize fire danger.
One of the most important aspects here is material. For the most part, Ethernet cables are either pure copper or a mix of copper and aluminum. Cables with aluminum run much hotter and struggle to pass ETL and UL safety standards. So, a cable on either list is almost certainly pure copper. Even if it isn’t, it’s such a blend that you don’t have safety concerns.
Specifically, ETL and UL both look at safety performance for Ethernet cables running on the ground, under the ground, and inside of building walls. They also test heat and fire issues for PoE-rated cables.
Across the board, if you see either seal, you know you have quality cables that are up to the task.
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