Haz-Mat Survival Tips: Beyond the Rule of Thumb

Survival Tip 11: Responding to Spills of Home Heating Oil

by Steven De Lisi

It’s winter and first responders in many parts of the country will once again be faced with incidents at residential occupancies that involve spills of heating oil. Perhaps an aboveground tank was overfilled by an inattentive delivery driver, or a tank that is placed on cinderblocks topples over due to the weight of the liquid. There are other occasions when a home will receive an automatic delivery at the start of each heating season, yet since the last time the tank was filled, the homeowner had installed a heat pump and removed the heating oil tank from his basement (but not the fill pipe) without informing the delivery company. The result could be several hundred gallons of oil pumped into the basement of the residence.

Another scenario includes situations when the fill pipe for an underground storage tank is broken off at the base and the tank fills with water during a heavy rainstorm. The result is a fast spreading oil slick that appears on the ground as the tank fills with water and displaces the oil.

During any incident that involves home heating oil spilled inside of a residence (including the crawl space underneath a residence), first responders should give careful consideration to any decision that allows occupants to remain inside. Besides the potential for a fire hazard, the vapors produced by the oil can have varying health affects on the occupants and on firefighters. First responders entering a building exposed to vapors from home heating oil should always consider the use of SCBA and take efforts to control ignition sources. They should also anticipate that indoor spills can enter floor drains and when this occurs, they must determine if these drains are connected to the local sewer system or perhaps nearby septic tanks.

For spills that occur outdoors, first responders should be prepared to use available resources in order to contain the release from spreading to nearby exposures. Remember that exposures include those below the surface, such as wells for domestic water supplies and septic systems. Even underground utility cables can be damaged if they become soaked with oil. Use caution if attempting to dig a retention area in soil to contain spilled liquid, since underground utilities, including electrical and gas lines, could be located dangerously close to the surface.

During severe weather, especially heavy rains, efforts to contain spills of home heating oil outdoors will be difficult, if not impossible. With this scenario, an oily sheen from the spilled fuel may spread across property lines, and as a result, the impact on neighboring occupancies must be assessed.

Stopping a release from a damaged or overturned tank will likely require the skills and equipment possessed by hazardous material teams. However, first responders should not be surprised if they encounter employees from a fuel oil delivery company who are attempting to use makeshift means to stop a release from an aboveground tank with little regard for their own personal safety. Despite the best intentions of these individuals, first responders should discourage this type of activity.

Cleanup related to spills of home heating oil that occur outdoors will likely require the removal of several inches of contaminated soil. Indoor spills may require vacuuming or use of absorbent pads to remove product, and perhaps even the removal of porous surfaces that allow the fuel to be absorbed, such as concrete floors found in basements and garages.

Regardless of the extent of cleanup required, the important point for first responders to remember is that it should not be their responsibility to figure out how the cleanup should be done, who will conduct the cleanup, who will pay for it, and then ultimately to determine when cleanup efforts are adequate and the scene rendered safe. Instead, these questions are best answered by representatives from various regulatory agencies, including those responsible for the environment and public health. First responders may even consider involving the local fire marshal if there are concerns related to code compliance regarding installation of heating equipment.

Financial liability for cleanup and scene restoration often rests with the responsible party. However, the responsible party may not always be just the fuel oil delivery company, but it could also be the property owner or even a tenant for rental property. The debate over just who is “responsible” can be complicated and it is best for first responders to stay out of this argument.

When dealing with cleanup issues, don’t be surprised if employees from the company delivering the heating oil either attempt to downplay the severity of the incident or attempt to conduct cleanup on their own rather than use a cleanup contractor. While allowing the oil company to conduct its own cleanup may seem like a simple solution, determining if employees from the company are legally qualified to conduct cleanup operations may require the involvement of state occupational safety representatives. Furthermore, their plans for disposal of contaminated material (such as absorbent pads or soil), must be done in accordance with applicable regulations. Once again, representatives from regulatory agencies should be the ones to determine if the company is qualified, not first responders.

While contacting individuals from different regulatory agencies may take some time to coordinate, the extra effort is worth it since it reduces the liability of the fire department should any problems arise later on. First responders should know how to contact these representatives after normal business hours, and on holidays and weekends. Remember that spills of home heating oil that occur on a late Friday evening can’t wait until Monday morning to be resolved.

Remember too that if first responders take it upon themselves to contact a cleanup contractor, they may also receive the bill. Therefore, decisions regarding selection of a cleanup contractor and financial liability should be left up to the responsible parties and the regulatory agencies discussed earlier.

When responding to incidents that involve spills of home heating oil, be smart, be safe, and remember, everyone goes home!

Discussion Points


  1. Has your department responded to incidents involving spills of home heating oil when members of the department became involved in cleanup activities or when their decisions resulted in financially liable for the cleanup? What were the outcomes?

  2. Has your department responded to incidents involving spills of home heating oil when first responders became ill following exposure to the vapors from the spilled material? How did these exposures occur and what were the outcomes?

  3. Do members of your department know how to contact representatives from the following agencies during incidents that involve spills of home heating oil:

    • Environmental Protection

    • Public Health

    • Fire Marshal (local or state)

    • Occupational Safety


    Could they contact these individuals at night or on weekends and holidays?

Click here for more info on Steven De Lisi’s book, Hazardous Materials Incidents: Surviving the Initial Response.

Steven M. De Lisi is a 26-year veteran of the fire service and is currently Deputy Chief for the Virginia Air National Guard Fire Rescue located at the Richmond International Airport. De Lisi is a Hazardous Materials Specialist and chairman of the Virginia Fire Chiefs Association’s Hazardous Materials Committee. He is also an adjunct instructor for the Virginia Department of Fire Programs and a former member of the NFPA committee on hazardous materials protective clothing. De Lisi began his career in hazardous materials response in 1982 as a member of the HAZMAT team with the Newport News (VA) Fire Department. Since then, he has also served as a Hazardous Materials Officer for the Virginia Department of Emergency Management and in that capacity provided on-scene assistance to first responders involved with hazardous materials incidents in an area that included more than 20 local jurisdictions.

Haz-Mat Survival Tips – Beyond the Rule of Thumb

Survival Tip 7- Class B Foam: Dilution Ratios and Applications Rates

By Steven De Lisi

There are several types of Class B foam concentrates available for use by first responders. These include concentrates referred to as protein, fluoroprotein, and aqueous film forming foam (AFFF).

Protein and fluoroprotein foams generally produce relatively thick foam blankets while AFFF foams often produce a thinner, more fluid blanket. This characteristic of AFFF usually allows for a quick knockdown of a fire as the foam spreads more rapidly across the burning fuel surface, yet this same feature may not be as effective in preventing re-ignition as are the thicker protein and fluoroprotein foams.

While most foam concentrates are intended for use on “nonpolar solvents” that will not mix with water, such as hydrocarbon fuels including gasoline, diesel fuel, and jet fuels, some are intended for use on “polar solvents,” or flammable liquids such as alcohols that will mix with water. First responders should be aware that the 2004 Emergency Response Guidebook (ERG2004) refers to foam for polar solvents as “alcohol resistant” foam and foam for nonpolar solvents (such as hydrocarbon fuels) as “regular foam.”

All foam concentrates are intended to be diluted, or proportioned, at varying percentages with water as determined by their manufacturer. Dilution ratios of 1%, 3%, and 6% are found most often. Once a foam concentrate is mixed with the appropriate amount of water, the result is usually referred to as a foam solution.

For example, 3% foam means that every 100 gallons of foam solution will require 3 gallons of foam concentrate diluted with 97 gallons of water. Using the ratio of 3%, 15 gallons of foam concentrate diluted with 485 gallons of water will produce 500 gallons of foam solution.

A foam concentrate with a dilution ratio of 1% means that 1 gallon of concentrate is diluted with 99 gallons of water. Using this lower ratio, only 5 gallons of foam concentrate would be diluted with 495 gallons of water in order to produce 500 gallons of foam solution. Some AFFF foams are referred to as 3% / 6% meaning that the foam can be used at either dilution ratio, depending upon the type of application.

For example, a manufacturer of foam concentrates may recommend a dilution ratio of 3% for fires involving nonpolar solvents and a higher dilution ratio of 6% for use with polar solvents.

The minimum application rate determines the rate at which a foam solution is applied to the surface of a flammable liquid spill, usually measured in gallons per minute per square foot of spill surface. These rates provide first responders with information regarding not only how much foam concentrate and water is needed to control and extinguish a fire, but also the minimum nozzle flow rate required when applying the foam solution.

Rates discussed here apply only to spill fires involving flammable liquids, defined as a spill that is not contained in a dike with an average depth that does not exceed 1″, and that is bound only by the contour of the surface on which it is lying. As stated earlier, the dilution ratio of foam is determined by the manufacturer of the foam concentrate used while minimum application rates are available from the National Fire Protection Association (NFPA) Standard 11, entitled Low, Medium, and High-Expansion Foam, and are dependent upon the type of foam concentrate used.

For example, when using AFFF foam for non-diked spill fires, the recommended minimum application rate is .1 GPM per square foot of spill surface. Other types of foam, such as protein and fluoroprotein, require higher minimum application rates of .16 GPM per square foot of spill surface.

With knowledge of minimum application rates, how much foam concentrate and water would be needed for certain size spill fire? Furthermore, what would be the largest spill fire that first responders could likely extinguish with the foam concentrate and water carried on their apparatus?

As an example, when using AFFF foam, remember that the minimum application rate is .1 GPM per square foot of spill surface, so that a 600 square foot spill fire would then require the application of 60 gallons of AFFF foam solution (600 multiplied by .1) for every minute of application. But how many minutes of application are required?

According to NFPA 11, first responders attempting to extinguish a spill fire should be prepared for a minimum discharge time of 15 minutes. Therefore, this same scenario would now require a minimum application rate of 60 GPM for 15 minutes, or a total application of 900 gallons of AFFF foam solution. First responders could easily meet the minimum recommended application requirements from NFPA 11 using apparatus with a 1,000 gallon water tank.

However, because foam solution is a product of water and foam concentrate, the question then becomes, “How much concentrate is needed?” That answer depends upon the dilution ratio of the concentrate used.

If using a 3% foam concentrate, remember that every 100 gallons of foam solution will require 3 gallons of foam concentrate diluted with 97 gallons of water. With the above scenario that requires 900 gallons of foam solution for 15 minutes of application, first responders would then need 873 gallons of water (97 x 9, or 97 gallons of water for every 100 gallons of foam solution) and 27 gallons of foam concentrate (3 x 9, or 3 gallons of concentrate for every 100 gallons of foam solution). Table 1 provides a summary of these calculations.

Table 1

Requirement for 3% AFFF Foam Concentrate and Water
to Extinguish a 600 Square Foot Spill Fire
1. .1 GPM / sq ft x 600 sq ft = 60 GPM of foam solution (application rate)
2. 60 GPM x 15 minutes (*) = 900 gallons of foam solution (total amount of foam solution)
3. 900 gallons of foam solution x .03 (3% concentrate) = 27 gallons of foam concentrate
4. 900 gallons of foam solution x .97 (97% water) = 873 gallons of water
(*) Minimum discharge time required by NFPA 11 (2005 edition)

First responders should know that any attempt to extinguish a flammable liquid spill fire that exceeds their capabilities (either in terms of water, foam concentrate, or application rate) could result in them being unable to gain control of the fire. Survival Tip 8 will provide guidance for preplanning foam fire suppression capabilities in order to avoid this problem. When determining the appropriate dilution ratios and application rates for Class B foams, be smart, be safe, and remember, everyone goes home!

Discussion Points
1. Determine the type(s) of foam concentrate used by your department.
2. Determine the dilution ratio(s) and minimum application rate(s) for each type.
3. Contact a representative from your department who is a member of your community’s Local Emergency Planning Committee (LEPC). Request to know if there are any locations in your community that use, store, or manufacture “polar solvents,” and if so, the quantities involved. Are these commodities also known to be transported through your community on highway or rail? Does your department have “alcohol resistant” foam concentrates available?

National Fire Protection Association, Standard 11, Low, Medium, and High-Expansion Foam (2005),
Section, A.5.8.
Ibid., Table 5.8.2.2.
Ibid.
Ibid.

For information on Steven DeLisi’s book Hazardous Materials Incidents: Surviving the Initial Response
go to: store.pennwellbooks.com/hamainsuinre.html

Steven M. De Lisi is a 26-year veteran of the fire service and is currently Deputy Chief for the Virginia Air National Guard Fire Rescue located at the Richmond International Airport. De Lisi is a Hazardous Materials Specialist and chairman of the Virginia Fire Chiefs Association’s Hazardous Materials Committee. He is also an adjunct instructor for the Virginia Department of Fire Programs and a former member of the NFPA committee on hazardous materials protective clothing. De Lisi began his career in hazardous materials response in 1982 as a member of the HAZMAT team with the Newport News (VA) Fire Department. Since then, he has also served as a Hazardous Materials Officer for the Virginia Department of Emergency Management and in that capacity provided on-scene assistance to first responders involved with hazardous materials incidents in an area that included more than 20 local jurisdictions