Ethanol-Blended Fuels: The Basics


We have all heard the cliché “What you see is what your get.” In the case of ethanol-blended fuels, that is not entirely the case. Because of the high ethanol (alcohol) concentration, you are dealing with an alcohol fire instead of the type of fire you usually encounter. Thus, you need to understand some basic considerations before you approach an incident involving an ethanol-blended fuel.


According to the Renewable Fuels Association, the estimated ethanol production in the United States was nine billion gallons in 2008. In turn, there is also an initiative that calls for blending ethanol into all consumer gasoline distributed. Most likely, the gasoline in the vehicle you are driving now has at least 10 percent ethanol blended into it. If not now, it will be soon.

Ethanol is being produced by 179 operating ethanol bio-refineries across the United States; most of them are in the heart of the Midwest.1 Virtually all of these plants are distilling corn to produce 200-proof ethanol. From there, the ethanol is denatured with five percent natural gasoline so that it can be shipped to refineries and distribution facilities across the nation as E-95 to be blended down to E-85 and E-10. Hence, we are now beginning to see problems with the shipping and storage of this fuel.

The processing of ethanol fuels includes the following steps:

1. Manufacture at ethanol bio-refineries that produce 200-proof alcohol, which is then denatured to E-95.

2. Transportation of ethanol (both neat and denatured) by highway/rail to users and distribution facilities. Important note: There is a push in the pipeline industry to start shipments throughout the nation’s pipelines.

3. The blending of gasoline to E-85 is handled at the petroleum marketing terminals/distribution facilities.

4. Cargo tank trucks bring the fuel to the “gas station.”




Ethanol is shipped by cargo tank truck transport or rail to a refinery for blending. A shipment of E-95 is identified with a red placard with “1987” (photo 1).

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(1) The placard for E-95 fuel. [Photo courtesy of the Minnetonka (MN) Fire Department.]

However, shipments from the refinery to the filling stations often may be misleading. It is not necessarily the shipper’s fault: Multiple chemicals with similar hazards shipped in the same compartmented cargo tank can be placarded to represent only the product that presents the greatest hazard. Hence, a truck carrying E-85 in one of its four compartments may carry the E-85 red “1203” placard. You will still be able to see all of the products being transported from the shipping papers. Note: The big difference between gasoline and E-85 and E-95 is water solubility.

Now a new standard is in place for the placarding of E-85. The placard will read “3475.” However, compliance with this standard is voluntary up until October 2010; it will then become a mandate. At an accident, prior to engaging in firefighting activities, do your best to find out what blend of products is being transported. If it is E-85 or greater, proceed with caution in applying foams or water spray, as the 2008 Emergency Response Guide #127 suggests.




Do you have a rail line in your community? Have you seen long trains traveling through your community with a large number of liquid storage cars? Or have you noticed that a number of those liquid cars are being parked in your community? If so, pay close attention.

Storage of ethanol is now a hot topic in the fire service. Why? The ethanol production facilities do not have the room to store large quantities of E-95. Typically, as fast as they can produce it, they ship it. When facilities produce more than 100 million gallons annually, that means one million gallons move out of the ethanol facility every three days. The refineries have a limited number of storage tanks and areas for the E-95, creating issues for many communities. With ethanol production greatly increased over the past five to six years, storage locations have begun to emerge in communities along old rail lines or side tracks.

Just outside Minneapolis, Minnesota, more than two million gallons are stored in railcars that sit in the backyards of homes, businesses, a large hospital, and two major highways. This problem is not unique; it is becoming more and more common in large and small communities across the country.

The challenges to the fire service, beyond the storage of the large quantities, are security, fire department access, water supply, and foam.




This is as basic as it gets: When you add water to ethanol-blended fuels, you force the separation of the gasoline and ethanol. What you are left with is gasoline on the surface and an ethanol/water and a slight amount of gasoline below (photos 2-3).

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(2) E-85 with no water.

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(3) E-85 with water added. (Photos 2-3 by author.)
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(4) The gasoline vaporizes or burns off first, and you are left with an ethanol (alcohol) fire hazard. At this point, if the product is on fire and it is daylight, you run a high risk of not being able to see the flame. Alcohol is clean burning; there is no black smoke. (Photo by Crawford Wiestling.)

In the tests in photo 3, approximately a half gallon of E-85 was dumped in the pan, and water was added. Note: It does not take a 1:1 ratio for the separation to happen. It can happen with a small amount of water. The pan was ignited and allowed to burn until it self-extinguished. After about four minutes of burn time, fire visibility started to change. Notice the lack of visible flame. After allowing this to burn longer, it was noticed that the flame was not visible at all, and there was still fire above the liquid surface.

Where does the water come from? By default, many departments use water, as suggested in the ERG. In addition, the foam applied dehydrates, and the ethanol absorbs the water. You must ensure you are using the correct foam concentrate (e.g., alcohol-resistant concentrate), applying foam at the proper concentration, and using the most appropriate application method.




The lack of visibility of the flames and the potential failure of a container/tank car are the greatest risks to firefighters when battling an E-85 or E-95 fire. Identification is the challenge. There are only a few ways to tell if the fire is actually there. First, look and listen. If you see a rough liquid surface and hear a boiling sound, you may have fire above the surface of the fuel. Use the thermal imaging camera. You will see a difference in heat immediately when the camera2 is looking at the spilled area. Finally, with a straw broom or paper taped to the end of a stick between you and the spill area, approach the spill slowly from a distance. If the straw starts to smoke or burn, back away. Of course, do this while wearing full personal protective equipment and self-contained breathing apparatus.




Many firefighters say, “OK, we will not add water; we will just use Class B firefighting foam.” Let’s look closer at the foam issue. What types of foam do you have on hand? How much? To fight an ethanol-blended fuel fire, only an alcohol-resistant aqueous film-forming foam (AR-AFFF) is recommended. An excellent study, Response to Ethanol-Based Incident—Foam Performance Test Results,3 a joint project of the Ethanol Emergency Response Coalition (EERC), the Renewable Fuels Association, and Ansul Technologies, discusses an Underwriters Laboratories 172 test of all of the foam families against E-10 and E-85.

There are many types of foam concentrates on the market. We all know of the Class A and Class B foams. Within the Class B foams, there are two main types, aqueous film-forming foam (AFFF) and alcohol type concentrate (ATC)-AFFF. Other foams in the newer technology arena would be Class A/B foams, which can be used on both types of fires. Some of these Class A/B foams have been successful in extinguishing E-85 and E-95 fires. However, they are not necessarily listed for alcohol-based fuels; you may need to apply the foam at an increased rate for ethanol when comparing it with a traditional Class B foam. Fire departments across the United States are purchasing the A/B foam as a solution to both classes of fires, since they do not want to budget for both types.

In this specific study, the EERC tested numerous brands of foams and concentrations. The tests concluded that in the typical firefighting approach of indirect or gentle application of a Class B foam, only the AR-AFFF passed the parameters for E-85. AR-AFFF and AFFF did extinguish an E-10 fire, but the AR-AFFF needed an increased application rate to pass the burn back test, and the AFFF failed the burn back test. The report concluded: “Overall, AR-AFFF proved to be the most effective and most versatile agent tested. It was the only agent that was successful in all fire test scenarios.”3 When selecting foams, ensure that they have passed a UL 172 test. The report and a video of the tests are at

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Departments should look at their needs based on a risk assessment profile from their response districts. This assessment should also identify the most likely large spill scenario. From this, you can estimate how much foam to have on hand. National Fire Protection Association (NFPA) 11, Standard for Low-, Medium- and High-Expansion Foams, Table provides some guidance on quantity. For alcohol fires, the recommended application rate is 0.30 gallons per minute/square foot (gpm/sq.ft of spilled area with a minimum discharge time of 15 minutes, as per the manufacturer). Currently, NFPA 11 looks to the foam manufacturer to identify the proper application rate when dealing with an alcohol-based fuel.

The following are the key points:

  • You are most likely to encounter ethanol-blended fuels in a spill scenario rather than a storage tank scenario.
  • Polar (water-soluble) solvents and ethanol-blended fuels require a higher foam application rate than hydrocarbon fuels or “regular” gasoline. Where NFPA 11 provides a recommended application rate of 0.16 gpm/sq.ft.hydrocarbon fuels using portable application devices, the recommended application rate for polar solvents and blends can be 0.30 gpm/sq.ft. or higher. Consult the foam manufacturer’s recommendations.
  • NFPA 11 recommends a foam application duration of 15 minutes for spill scenarios and 65 minutes for aboveground storage tanks containing Type I flammable liquid.
  • Application of Class B firefighting foams onto polar solvents and blends is much more critical than with hydrocarbon fuels. Firefighters should apply Class B foams as gently as possible to minimize coating or submergence of the finished foam.





The keys to safely responding to incidents involving E-85 or E-95 as recommended by the 2008 ERG are the following:

  • An initial 150-foot isolation.
  • If a large spill, then 1,000 feet in all directions.
  • If a rail or tank truck is on fire, then a ½-mile evacuation.
  • Acquire shipping papers to confirm product identification.
  • If foam is going to be applied, use AR-AFFF.
  • If there are no exposure issues, let it burn.





Response to ethanol-blended fuels can present many challenges. The leading safety concern for firefighters, as noted above, is the lack of flame visibility in daylight conditions if the gasoline and ethanol have separated with the application of water. This article addresses the basics of an approach to this type of incident. Keep it simple, and approach cautiously.






3. “Response to Ethanol Based Incidents-Foam Test Results,” Ethanol Emergency Response Coalition, 3.

GREG HAYES is an 18-year veteran of the fire service and a captain with the Roseville (MN) Fire Department. In addition to a fire background, he has expertise in hazardous materials and emergency preparedness. Hayes is an instructor within the Minnesota State Colleges and Universities system, where he teaches hazardous materials response and emergency preparedness.


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