(A segmented look at Firefighting, Fire Extinguishing Products, and Fire Suppression)
We’ve looked at firefighting
foams and now we’ll look into long term retardants and What’s Being Done…
What are long term retardants?
Quite simply it’s the red stuff dropping from aircraft across the world on wildfires! So let’s look at the technical side of Long Term Retardants…
A fire retardant is a substance other than water that reduces flammability of fuels or delays their combustion. This typically refers to chemical retardants but may also include substances that work by physical action, such as cooling the fuels or by initiating a chemical reaction that stops a fire.
Early fire retardants were mixtures of water and thickening agents, and later included borates and ammonium phosphates. Borates are chemical compounds which contain oxoanions of boron in an oxidation state and ammonium phosphate is salt of ammonia and phosphoric acid. Today’s long term retardants are comprised of Diammonium Sulfate, Monoammonium Phosphate, Diammonium Phosphate, Guar Gum, Hydroxypropyl, and Performance Enhancers of Diammonium Sulfate is a synonym for Ammonium Sulfate and other synonyms are Sulfuric Acid, Diammonium Salt, Actamaster, Dolamin, and Mascagnite. Ammonium Sulfates are an inorganic salts which is part of soil fertilizers and its purpose is to reduce the soil pH.
Monoammonium Phosphates is an ammonium dihydrogen phosphate and is formed when in a solution of phosphoric acid is added to ammonia until the solution is distinctly acidic. Monoammonium phosphate is often used in the blending of dry agricultural fertilizers and it supplies soil with the elements nitrogen and phosphorus which is usable by plants. The compound is also a component of the ABC powder in some dry chemical fire extinguishers. This substance is also supplied in an emerald green or aquamarine crystal growing box kit for kids.
Diammonium Phosphate is used as a fertilizer and when applied as plant food, it temporarily increases the soil pH.
Guar Gum, Hydroxypropyl is an inert ingredient used as a thickener. Its common characteristic is that it’s a water absorbing polymer.
Ok that sounds pretty technical and that’s what’s in the red stuff... What are its effects on the environment?
Well according to the manufacturer they say it’s…
“Long-term retardants are the safest, most effective, and environmentally friendly retardants available. No other products meet the current USDA Forest Service specification for long-term retardant. This specification includes product qualification testing for combustion retarding effectiveness, environmental, safety and health and corrosion standards.”
Ok so the manufacturer states that its product is the safest, most effective, and environmentally friendly and no other product meets the US Forest Service Specification. Hmmmm lets have a look at that…
According to the USFS Qualified Products List they are correct! There are no other companies listed on the QPL with a product that is classified as a long term retardant… So they are a sole source provider to the Federal Government...
So how effective are long term retardants?
There are no public records with the US Forest Service for Lateral Ignition Flamespread Test or Combustion Retarding Effectiveness. So the answers are unknown to the public...
Let’s recap what we have learned so far. Chemical composition is very salty with fertilizer salts. Here is a breakdown according to the MSDS sheet listed with the US Forest Service.
Diammonium Sulfate, CAS #7783-20-2 = >65%
Monoammonium Phosphate, CAS #7722-76-1 = >15%
Diammonium Phosphate, CAS#7783-28-0 = >5%
Guar Gum, Hydroxypropyl, CAS#39421-75-5 = Performance Additives, CAS# Trade Secret = The trade secret performance additives are protected by “trade secret” but the manufacturer states “Our wildland fire retardants consist of fertilizer type salts, a coloring agent, corrosion inhibitors, and flow conditioners.”
Ok so there are corrosion inhibitors in the red stuff well what are they?
In an environmental assessment of long term retardants dated October 2007 conducted by the US Forest Service it states ” Previous retardant formulas contained sodium ferrocyanide 2 as a corrosion inhibitor. It was found that under certain conditions, sodium ferrocyanide poses greater toxicity to aquatic species and aquatic environments than retardant solutions without this agent.” While we cannot confirm what corrosion inhibitors are currently being used today in the current formulas because they are a “trade secret”. One can only assume that they have not improved since 2007 and here is why…
In July 2010 a Montana Federal Court Judge the Honorable Donald Malloy “ordered the U.S. Forest Service to take a hard look at its use of toxic aerial fire retardants and their impact on fish and wildlife habitats.”
Ok so that blows the claim by the sole supplier to the Federal Government that they are the “safest, most effective, and environmentally friendly retardants available.”
Hmmm, no testing results available on effectiveness. So the “safest, most effective, and environmentally friendly retardants available” on the market today?
Not so much according to the environmental watchdog groups who filed a federal lawsuit and not according to a federal judge.
So What’s Being Done?
“Molloy ordered the Forest Service to comply with the federal laws by Dec. 31, 2011, threatening contempt sanctions if the agency fails to do so.”
"The Federal Defendants are advised that failure to comply with this deadline may subject them to sanctions, including contempt proceedings, and could conceivably result in enjoining the continued use of aerially-applied fire retardant until the law enacted by Congress is complied with," Molloy wrote. "The issue requires immediate attention."
That was July 2010 and in December 2010 headlines are;
“U.S. District Judge Donald Molloy of Missoula” announced “that he will be taking senior status in August 2011.”
Coincidence??? Guess we will have to wait and see…
So who is the manufacturer of the sole provider of products used by the Federal Government to retard and combat wildfires?
They are called Phos-Chek and the Phos-Chek Fire Safety Group is part of ICL Performance Products LP, North America's premier phosphate chemical manufacturer.
So who is ICL?
“ICL Performance Products LP is a worldwide leader in the manufacturing and marketing of phosphates, phosphoric acid, and phosphorus chemicals.”
Since it is a Limited Partnership company is there a bigger picture or group?
“ICL Performance Products LP, headquartered in St. Louis, Missouri, is a wholly owned subsidiary of Israel Chemicals Limited (ICL), based in Tel Aviv, Israel. ICL is engaged in the development, manufacture and marketing of fertilizers, industrial products, metallurgy, and performance products.”
So during this segment we discussed long term retardants and the jury is still out on them. We have also looked at firefighting foams more commonly known as Class “A” foam used for fire suppression. In the next segment we will look at fire gels or water enhancers and how they affect firefighting equipment, the environment and the effectiveness for fire suppression or exposure protection.
By: Rob Rosovich, Fire Protection Engineer