Non-Road, Locomotive, and Marine Diesel Fuels (NRLM)

Aka. Off-Road, Off-Highway Diesel Fuels

The recent EPA mandated changes to Off-Highway or Off-Road Diesel have not been well reported to users of these fuels.

The little information that is available is extremely confusing and often contradictory.

Here we will try to provide some accurate and useful information that will allow you understand what is happening and allow you to make informed decisions.

As of June 2007 Off-Highway fuels have been designated by the EPA as ?Non-Road, Locomotive, and Marine? (NRLM) fuel. This is fuel used in Off-Highway diesel engines for Construction, Agricultural, Stationary Engine, Locomotive, and Marine operations.

NRLM fuel is going through several changes or steps on its way to being 15 ppm or less of sulfur.

Starting in June of 2007 NRLM (LSD, S-500) is required to contain 500 ppm of Sulfur or less.

This means that Home Heating Oil (HHO), Industrial Fuel Oil (IFO), Marine Fuel Oil (MFO) (Marine Fuel Oil is different from and not to be confused with Marine Diesel Fuel), and Jet A (when used for Aviation) are the only fuels allowed to have sulfur content higher than 500 ppm.

In most of the US the EPA now requires distributors to add a new dye known as Yellow Marker 124 to HHO and IFO fuels. This dye is not usually visible to the naked eye when mixed with these fuels. It is being added to these fuels to provide a way for enforcement agents to be able to tell out in the field if high sulfur fuels are being used in any type of engine. There is a fine structure in place that starts at $32,500.00 per incident, per day for use of fuels containing more than 500 ppm of sulfur in any diesel engine.

Note: This change has already happened, this fuel is being, and has been delivered to these users sine June of this year. If you are using any high sulfur fuel in any engine, you are subject to enforcement.

Now here is where it gets complicated. NRLM (LSD, S-500) is currently defined by the EPA as diesel fuel containing 500 ppm of sulfur or less.

NOTE: There is no minimum amount of sulfur required in NRLM or LSD.

This is important because many (most) fuel distributors do not have enough segregated storage available to keep all of the fuels required to supply every possible need. Also in most of the US high sulfur fuels now have the Yellow 124 dye in them which prevents them from being downgraded by the addition of ULSD to create NRLM.

In many, if not most areas of the US, suppliers have storage for ULSD and HHO (including HSD) and Kerosene. However they may not (the majority do not) have segregated tanks available for NRLM and ULSD #1.

What this means to all of the agricultural, construction, and other users of Off-Highway (NRLM) fuel is that your fuel supplier can legally sell ULSD (fuel with 15 ppm or less of sulfur) to you and call it Low Sulfur (S-500, NRLM).

It is perfectly legal to do this because 15 ppm, 10 ppm, 5 ppm, even 0 ppm diesel is all less than 500 ppm which is all the law requires.

Why all of this is important is because the processes (Hydro-Cracking, Hydro-Desulphurization, and Severe Hydro-Treating) used to remove sulfur from fuel also remove other components.

The most important of these are Lubricity and Aromatic content. The Lubricity of Low Sulfur Diesel (LSD) or NRLM is approximately 30% lower than the old High Sulfur Diesel (HSD). The Aromatic content is lowered by approximately 10%.

These reductions are what the On-Highway or On-Road users suffered through back in 1993. The lower Lubricity causes increased wear and failures in diesel injection pumps and in fuel injectors. The lower Aromatic content causes rubber and other materials used in o-rings, seals, and gaskets to shrink, dry out, and eventually crack and fail.

This problem, as bad as it is; is made much worse by the problem mentioned earlier. It is difficult enough for an engine (the older the engine the more difficult) to accept a change from High Sulfur Fuel (HSD) to Low Sulfur Fuel (LSD, NRLM), but when you consider that NRLM (LSD) may actually be USLD which has Lubricity that is another 50% lower and Aromatic content another 10% lower, the potential for increased wear of metal parts in pumps and injectors, and failure of seals and gaskets is potentially a huge problem.

This problem gets more complicated as we go forward. In 2010 NRLM fuels will split for  two years with Off-Highway (agricultural and construction) going from 500 ppm or less to 15 ppm or less of Sulfur and the Locomotive and Marine fuel staying at 500 ppm.

Then in 2012 the NRLM fuel for Locomotive and Marine goes to 15 ppm or less.

This overly complicated process and the lack of information being offered can lead to very expensive problems for ALL users of diesel fuels.

There is something you can do right now to protect your equipment and prevent or reduce these problems.

Enertech Labs offers a wide range of products for all fuels. Our Complete Fuel Treatment? will provide enough of the highest quality synthetic Lubricity agent available today to bring the Lubricity of NRLM and ULSD fuels back to the level of the old High Sulfur Diesel (HSD). Additionally Complete Fuel Treatment? contains components to protect seals and gaskets from drying out, provides fuel system cleaning, oxidative and thermal stabilizers to improve storage life, a water dispersant to remove dissolved and liquid water, a Cetane Improver, and the most advanced Anti-gel package on the market today.

Contact Enertech Labs today for more information on this and other products to protect your investment and to make your operation easier and more profitable.