I am installing a new service for an outdoor bulk diesel fuel storage plant. It will be used for distributing fuel by the companies truck only (No customer access). I am looking for the distance that the service will need to be placed away from the tank and equipment so that it can be unclassified. I was thinking that it was somewhere around 30-35' but what I am reading in the code book (Art. 515), is telling me 15'. Is this correct?

Diesel fuel / fuel oil is not usually considered to pose a risk of explosion.

Where there are such concerns, you worry about distance from vents and such - not the tank itself.

As a storage facility, you can't even call the place a 'motor fuel dispensing facility.'

Merlin:
Reno is on the right track with the diesel.

I will add that you should check with your local electrical inspector, and the fire official.

Understood, but the motor and controls still need to be explosion-proof, correct? It is still a flammable liquid that could pose a risk of fire. I am looking for some documentation in case the inspector attempts to challenge me.

You have to be certain that no other fuels/ risky items are involved.

If that is so, middle distillate -- aka Diesel fuel is entirely unlike gasoline -- being even heavier than kerosene.

(Longer chain molecules, lower vapor pressure.)

It's for this reason that middle distillate is THE fuel of choice for marine engines -- unless they are out board engines.

The entire rationale for an outboard engine is that they can tolerate gasoline -- in as much as the engines are out board of the craft -- and the vapors are dispersed as a result.

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So, the vapor hazard is quite low.

I would still expect to see robust materials used.

The mechanical stresses imposed upon all systems in such a rough use situation is determinative.

As you might imagine: such materials are pricy.

On the economics, it's kind of hard to believe that any firm actually wants to set up its own distribution node.

The normal, economic, practice is to hook up with an outfit that dispenses such fuels to such accounts on a bulk basis.

SOME Diesel operators are now pushing towards dual fuel rigs which start up on pure Diesel/ middle distillate -- and then blend in natural gas/ methane after warm up.

The pollution reduction, service life extension (it's a clearer burn -- by far ) and reduced fuel expense is compelling.

I can't remember the fellow, but at least one billionaire is setting up MAJOR distribution nodes around America's freeway system for class 8 rigs for just this reason. Until crude oil prices broke lower, his grand scheme was THE way to go.

I'd have thought that your project would be a mirror image of his campaign: dual fuel.

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These dual fuel systems are up on YouTube.

https://www.youtube.com/watch?v=PqKg5hKuND0

The trucking industry is SO competitive that such fuel savings are enough to triple ones net profit per mile.

Paying off the conversion (not so cheap) does slow down the adoption of this dual fuel scheme.

IMHO, again I suggest contact your local AHJs. Particularly, the Fire Official.

The equipment that is intended to dispense the diesel will come with mfg instructions.