My team designs plumbing systems for hazardous locations for safety showers. These systems use components rated for the specific hazard and certified accordingly. The question I have, am I required to now get my assembled system certified for the hazardous rating or am I good using certified components? The testing agencies say I need to but then again they want more business from me.

Equipment used could be water heaters, space heaters, pumps, lights, horns, control panels, etc. Each job is different and therefore I would be required to certifiy each design seperatly prior to shipment.

Thanks for your insight.

That's kind-of a pain, but I think they're right. If you're brining something pre-fab to the site, the internal connections of all your equipment can be construed to be part of a manufactured system. It's in a category similar to building smoke evacuation control panels. Even if all the components in the panel are UL864, the panel itself will not be accepted unless it is labeled as a system.

Now, if you bring all those components to the site separately, you can maybe cut down on the approval mess. The way the fire alarm folks do it is to get a listing for a system with the maximum, full-blown set of options, with a declaration that any subset of the system will involve only deletions (and a schematic or chart of the possible permutations). If you have a listed water heater and a listed pump that are installed at the site in accordance with code for the classification, there isn't any need to include those in your listing. Perhaps only your power panel and control panel need the listing, in which case you can get your panel shop certified to build ad-hoc custom panels with a hazardous location certification. We can't be sure without a more detailed explanation (schematics, site construction sequence, etc...).

Good on ya,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

have a look at NEC 500.8 (A), Suitability
note that the list includes "evidence acceptable to the AHJ, including manufacturer's self-evaluation or an owner's engineering judgement"

In other words, it may depend on the inspector. With hazloc engine packages (my only area of hazloc experience) for Class 1 Div 2 areas, it is rare for an inspector to say that a system composed of marked/listed components installed per the mfr guidelines is not acceptable.

Of course it would be the best to have the whole package listed but I see your point that these are custom systems. If the system is not listed as a package then the local inspector will need to examine the whole skid to ensure the proper seals and wiring methods, etc. have been used to assemble the system. However, I don't know if many people get custom systems like this listed.