Having the “CE” Mark is NOT a substitute for what a UL, CSA or ETL mark does on a variety of levels.

First, it is mandatory, not voluntary, that products have the CE mark when sold in the EU. However, the difference is that the manufacturer themselves can test and self-certify the compliance.

Then there is the issue of the various CE standards that the application of the mark is certifying compliance with. These standards are considerably different from those of UL, which are typical in the US or CSA, which is used in Canada. These standards are for safety ONLY and have no bearing on how the product actually works/sounds. Rather, they are simply saying they won’t burn your house down, burn you when you touch them or cause a shock hazard. CE standards are quite different UL or CSA.

When it comes to the actual testing, although UL (which, contrary to what some may believe, is an independent, non-governmental organization) SETS the standards, compliance with them may be given by any “Nationally Recognized Test Lab”, or “NRTL”. The ability of labs other than UL’s own to do this was once the subject of legal action that, I believe, went all the way to the Supreme Court. That is why you see marks from different labs such as CSA (which also both sets standards and tests for compliance) ETL/TUV. There are other NRTLs that test a wide range of products outside of consumer electronics.

Look at the mark on a product and you’ll see two things. First, obviously, is the lab’s mark. Then, you’ll see a number BELOW the mark that is the number for the standard the unit is compliant with. You’ll also often see both a “C” and a “US”, particularly with CSA tested products, signifying that the product is compliant with both US and Canadian standards. Remember that testing and compliance with UL is NOT required for consumer electronics products, although in some jurisdictions it is required for display on shop floors.

What IS required is the FCC testing to confirm compliance with emissions standards or DHHS compliance for products with lasers. Take a look at the power brick for your laptop and since these are generally made for global compliance with these standards as they vary from country to country. There you get a world tour of compliance with things such as “CCC” for China, NOM for Mexico, “C-Tick” for Australia, Nemko, and many others.

On top of that, particularly outside of the US, there are requirements for the “wheelie” logo to denote recyclability (or not), RoHS, the “double insulated” indication, etc.
Safety and compliance is a detailed and technical world unto itself.

Bottom line: Having a “CE” mark is nice, and if the compliance was done it means the product is likely to be safe, but it means nothing in the US. Application of the mark of an NRTL and the applicable standard not only means the product has been tested, but in these cases there is also a plant inspection and follow-up visits to make certain that no changes have been made to any part that would require a re-certification. The day the “UL guy” shows up at your plant and asks to see the files is not a happy day.

As an aside, if you open a product (which, of course, the UL standards require that you put a warning in the manuals and on the rear panel telling consumers NOT to do!) you will see boards and components with a “UR” mark. That tells you that the board, chip, transformer or whatever is, itself, compliant with the applicable standards. (For example, that a PCB meets the “94V0” flammability standards.) However, while you need to use UR parts, or parts that otherwise have the necessary Certificate of Compliance “C of C”), that does NOT in and of itself mean that the product is approved or certified. That only comes when the whole system is tested. Having someone (and I’m NOT saying anyone discussed here does this) say that they use UR parts means that a product is approved, is simply not true. Haven’t seen or heard that in a while, but it has happened in years gone by.