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Looking at certifying, for the US market, a line of LED Drivers. Is ETL or TUVus accepted as much as UL by most end customers? Want to make sure I take the best route to supplying what the customers are expecting.


Hi buntknob,

My experience has been that ETL, MET, CSA, and TUV are growing in acceptance -- particularly in the electrical construction industry.  But they're not as universally accepted as UL.  You'll have to get some market data on your product's intended customers to see what's necessary.

This is especially true in consumer goods -- while you'll see major retailers selling major appliances (refrigerator for example) with an alternative listing, you won't catch them selling a plug-in desk lamp without UL on it...

That's just my experience, though. Let the others weigh in on this -- I'll be following this thread to learn more myself!

Be sure and post us with your end result...

Good on ya,

Goober Dave


From a manufacturer perspective there is a strong desire to pursue listing via alternative NRTLs (nationally recognized testing labs) due to the massive cost differences.  At the same time, UL is still the primary authority and the other agencies even perform their tests to the UL standards and publications.  In addition to costing less, the other agencies tend to be faster and more responsive.

I don't know about the other agencies, but UL has an active and continuous process of updating and improving the their testing standards.  They have a fleet of engineers and other personnel engaged in the process.  They hold meetings in which the primary manufacturers and other parties with a vested interest are invited and contribute to the creation of the standards.  They are currently involved in unifying the standards across North America.  Obviously this is a significant expense and is likely part of why UL is more expensive.  

On a personal note, having been involved in getting equipment listed through UL and other agencies, I think that the UL testing was more thorough.  Maybe this has to do with not feeling need to try and gain market share, which can be a conflict of interest.  As a result, I am personally more comfortable with a UL listing than another agency.


We use ETL for all products based on issues that have come up when we used UL in the past. We have found ETL to have a better understanding of the standards and how to apply them to our products versus UL. From past experience UL engineers "interpretations" of the standards can vary wildly among engineers. We can have one engineer look at our product and might find 20 supposed issues, another engineer will only find 3 issues. We have seen many times where our competition can do something and UL will allow it while they will red flag us for the same construction. There have been many times that we have been put at a competive disadvantage because our competition is allowed to do one thing where we must derate/modify our product to pass. (maybe we don't take them out to dinner enough or something). So UL initially costs more and we end up taking more of our own time to fight them on their interpretations which costs even more in the long run. ETL gets it right the first time.

As for who is more excepted in the industry, UL of course but our customers don't care who does our testing as long as we are all testing to the same standards and they all do.



We use TÜV to certify our products for essentially the same reasons as mcgyvr. We pursue listings year round and have an engineer dedicated to maintaining our file and another one or two who help out when necessary. UL would assign us another engineer every few projects and we would subsequently waste the extra week or so waiting for the new guy to work out a test plan that the previous engineer would see as straightforward.

The straw that sent us packing was 15 years worth of product evaluations suddenly being considered insufficient and their asking us to pay for retroactively retesting and recertifying of our entire product line to a new test plan that manager/engineers Northbrook who didn't know our application in detail insisted that the engineers in Santa Clara follow. I think they gave us 60 days to repeat $250,000 worth of testing or quit using the UL label altogether. That meant devoting an entire year's budget to recertifying and delaying certification of the new year's products until they were all but meaningless. What an obvious shakedown.

TÜV accepted UL's previous test data and assigned a specific engineer to reassess the conditions of acceptability that we argued made all the previous test plans appropriate. Some changes have been made but they didn't completely disrupt our business cycle.

It's really the market and the customer who calls the shots though. There's one who will accept Intertek and TÜV Rheinland but not TÜV America and the sales guy just rams it through. We lose money but he still gets his commission. It's not his budget. Gotta love creative accounting.


Funny this came up now.. We just had a customer yesterday who said we had to use UL. We then told him that we prefer ETL and that they are testing to the exact same standard. He was simply not aware that the other testing labs could even test to the UL standards and though they had their own. He now has no problem with us using ETL. Not to mention UL quoted double the price and double the time to complete testing.


I'd have to say "Ditto" to everything mcgyvr ha said.  Unfortunately our sales people usually demand the we use UL.  ETL is much easier to deal with and seem to be more consistant.


In general, I too agree with mcgyvr.  As I said in my earlier post: In addition to costing less, the other agencies tend to be faster and more responsive.  I too have seen the "interpretation" aspect of dealing with UL.  Part of this is the employees and part of this is the specs, which more often than not are vague and contain gaping holes.  For example, I saw a spec for a motor overload sensor / trip circuit.  It said that with a motor current under 300% full load it shall hold indefinitely.  Above 600% it shall trip at between 8 and 20 seconds.  It says NOTHING about what shall happen between 301% and 599%.

On the flip side: in one of our products at work, there was a manufacturing and purchasing mistake where the wrong MOVs were placed in the product.  The MOVs used had an insufficient voltage rating, which resulted in some ... sparks ... when operated on some units, but not all.  The product was evaluated and approved by ETL.  They did not catch that the MOVs were wrong.  From a personal perspective, this scares me, at least with regards to products that I may buy and put in my home.



Well, as others have mentioned, it's all about customer perception.  Many people do not realize that there are some ~17 NRTL's in this country.  They're still used to the old "UL = USA and CSA = Canada" mentality.  What matters to you is how your bottom line will be affected.  I'd suggest a comparison to competitor products and see which agencies they all use - is there one that stands out above others?  Is it a mixed bag?  This will tell you what the end users are used to seeing and most likely what they ask for (and end user survey or general market study may also help).  A little education can go a long way if you chose to use an NRTL outside of UL (by showing your end users that there's no difference, from a legal stand point).  I had to do this for my company when we switched all of our Canadian Listings from CSA to cUL.  There was some initial confusion at first, but now everyone is up to date.

As a compliance engineer, I agree with the different interpretation you'll get from different engineers at UL.  However, you see this with other agencies as well, just not as much.  If you have a compliance engineer on staff, there's no need to worry about this because he/she will straighten out any mis-interpretations and assumptions (a regulatory compliance engineer is worth his weight in gold!).  If you don't have one on staff, assign the certification part of your project to one individual (engineer) and encourage him/her to validate all interpretations and assumptions made by the agency engineers (easier for one person to keep it all organized vs several people).  Remember, the agency engineers are experts in the standards and codes, but only YOU are the expert in your product, its design and intended applications.  You have to work together with the agencies to prevent waste in the form of unneccessary testing and evaluation (and ultimately cost $$$).  I've also found that TUV tends to be very expensive, in some cases more than UL.  Good luck.

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