Class 1 Div 1 requirements and testing protocols

Hi Bill,

If your product is to be employed in the US --

If you're going the explosion proof route, you'll need a copy of UL 1203. If you're trying for intrinsically safe, you'll need UL 913.

You'll need testing, since your device does not qualify as "simple apparatus," which in and of itself neither stores nor produces energy.

UL can do the testing, of course, and so can Factory Mutual. A great number of others can also do it for lower prices -- METLAB, ETL, etc... See for a US list.

You'll need to deal with different standards and different "notified bodies" if you're looking into other markets outside the US. If so, wait for a bit and you'll get more responses from those abroad.

Good luck with your project, and let us know how it works out!


Best to you,

Goober Dave

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For the rest of the world you'll need IEC 60079; UL works with this standard too.

After you pick your approach to Class 1 Div 1 (intrinsically safe (IS), flameproof, pressurized, powder filled, etc.), you'll need the safety aspects documented fully before you get it certified. The acceptable voltages vary with the approach. From my first C1D1 project I learned that UL will be happy to take your data and your money for a preliminary review, and wait then about 14 weeks before they will tell you that it won't pass with only cursory reasons why; they won't help you fix it. If you haven't done this before you'll save a lot of time and effort by hiring a consultant/engineer who specializes in C1D1 to take this to the regulatory body for you. If you go IS then expect circuit changes to add the protection circuitry. Let me know if you are looking for a recommendation.

Z