04-09-2001, 09:35 PM #1SJNormanFirehouse.com Guest
Do Extinguishers hide accelerants
My name is Samuel James Norman. I am currently studying my 3rd year of a Bachelor of Applied Science (Forensic Investigation) at the Canberra Institute of Technology. Our 3rd year program includes a major practical project to be undertaken over six months. I intend to research whether the use of fire extinguishers causes any detremental effects on the ability to detect accelerants at crime scenes, and whether the fire extinguishers contain any chemicals which may falsly indicate accelerant when there was none actually present. I am interested to know if your company has undertaken any research in this field. I am also seeking a list of chemicals (whether ingredients or impurities) which are typically found in the different types of extinguishers available on the Australian market. Any information which could be passed on would be greatly appreciated.
04-15-2001, 02:00 AM #2eyecueFirehouse.com Guest
Since most of the extinguishers intercept the free radical and bind it so that it will not oxidize, There is no chance that a dry chemical extinguisher will give that reading. The same is not true for some types of foam. The ingredients in foam can give a false positive on accelerant tests.
04-15-2001, 12:42 PM #3reyfordFirehouse.com Guest
As always, it depends on how much flammable liquid accelerant was present before the extinguishing material was introduced and also how much extinguishing material was used. It has been my experience that a fire investigation canine can still always detect a flammable liquid under both dry powder and foam. They have the ability to discriminate similar odours whereas hydrocarbon detectors often do pick up other things that are present.
Robert Eyford, CFEI,CCFI, canine handler
04-15-2001, 01:30 PM #4CJBFireConsultantFirehouse.com Guest
Actually, I would beg to differ from Mr. Reyford in that he is not correct, at least not based upon US law or upon fire science studies. Poster: Eyecu is more correct.
The recent studies, US Court Cases, and even the MSDS Sheets and NFPA 921, all warn against the use of foam on fire scenes as the foam ingredients can and probably will lead to false positives on a fire scene. As to the acurracy and detection limits, the USBATF (Alcohol Tobacco & FireArms) has concise standards and guidelines by which the dogs must be trained and tested under.
Another warning issues was against the use of Positive Pressure Ventilation fans that area gasoline powered. Another successful arson defense was that spilled gasoline at the scene while trying to fill the fans', was tracked into the structure by the fire suppresion crews, thus again contaminating the fire scene with gasoline.
Your posting is interesting as there is a big debate right now in the fire ivnestigation community about the effectiveness of dogs. Check out the IAAI, International Association of Arson Investigators Website for more information on the postings. I would search for the keyterm DOGS, to maximize your findings.
The problem is that the ingredients of foam are hydrocarbon based, and any attorney worth a #$#$, can and will be successful in stating the fire scene was contaminated by the fire department and that is where the hydrocarbon "hit" by the dog came from.
Your better source for dog information is a very well known and internationally respected IAAI State President, George Wendt
. He not only uses dogs as tools, but also can assist you in the ATF guidelines and procedures for their training here in the US, and is in a better position to offer insights into areas where they are lacking expertise.
FYI: I personally have seen a TEST Structure, where an ATF certified dog went over and skiped a strong known "TEST MARKER" several times, and hit on areas where there were no tests hydrocarbons dropped. Dogs are tools, nothing more. The subject of the conclusions drawn by that tool, is a matter for interpretation by the hopefully properly trained dog handler.
This is not meant, by any stretch of the imgination, to be a critique of Mr. Reyford. However, here in the US, we are governed by far different standards and requirements than those of Canada. Also, there are far more encompassing court cases and challenges with respect to Spoliation of Evidence and Evidence Tampering and Contamination.
I trust this satisfies your request for more information
05-03-2001, 02:13 PM #5reyfordFirehouse.com Guest
Hold the phone Mr. Bloom!!! Go back to Mr. Norman's question. The question he is researching is "do fire extinguishers cause any detrimental effects on one's ability to detect accelerants and does the chemical used to extinguish the blaze falsely indicate the presence of an accelerant when none is actually present" One responder stated that the ingredients in foam can give a false reading, but not in dry chemical.
I responded that in my experience, my canine has always been able to find "FLAMMABLE LIQUIDS" whether under dry powder or foam. I stand by this as we do it regularly. Whether or not the foam or anything else has a "hydrocarbon" in it, is irrelevant, depending of course on what the hydrocarbon is. Hydrocarbons that are not flammable liquid are not alerted on by a canine who has been trained to detect certain flammable liquids while ignoring other hydrocarbons that are not flammable liquids.
Your comments about gasoline being tracked into the fire scene are noteworthy and well known but have nothing to do with the question put to us. I appreciate that recent studies warn against the possibilities of getting positive readings when foam has been used, but I must ask, "positive readings with what, an electronic hydrocarbon detector?. In that case I would agree that it may be possible, but it has been my experience that in most incendiary fires in which flammable liquid has been used, the flammable liquid has been used in large, as opposed to minute, quantities and a laboratory should be easily able to substantiate the alerts by the canine. Many people are under the false impression that a canine used for fire investigation alerts on all hydrocarbons. Part of the reason for this is that many people who are writing and speaking about the subject, as so called experts, don't know what they are talking about. In fact, canines only alert on hydrocarbons which are flammable liquids, assuming they have been properly trained as such. Your comments that an attorney will be successful in stating the fire scene was contaminated by the fire department because they used foam is only accurate if the foam contained a flammable liquid (which I doubt). In any case,the normal procedure (yes, even in backward Canada) is to take the suspect sample and send it to a laboratory for analysis. If that comes back as positive for say, gasoline, are you trying to suggest that test is invalid because there was foam in the fire scene that contained a hydrocarbon? The fire scene is in fact, full of hydrocarbons, such as carpet,foam underlay, plastics, etc.
With regards to your last comments about you witnessing a dog hitting in the wrong spot, I can see no reason why you would include that in this topic, other than to put down canines generally. I have never heard anyone suggest that a dog is more than a tool, yet the buzz word in the industry seems to be that "the dog is no more than a tool". It was never intended to be more than that nor ever suggested by anyone to my knowledge that it was more than that, so lets' all agree on that. It's only a tool.
Part of the problem with forming opinions about the canine in general is that most people who are evaluating them don't know much about them and are therefore easily misguided. For example, I gave a demo with mine on an occasion in some burn cells, some of which had a small amount of gasoline poured in them. Our demo consisted of searching each one and telling the class where each pour had been. The canine also hit on one location where there had not been a pour. Skepticism began to spread until one of the instructors remembered that in between pours, he had left the plastic gas can sitting in that location. I have learned not to argue with my dog. Had the instructor not spoken up, some people may have called that a false alert and decided the dog was useless. That may have happened in the case you mentioned, who knows.
Your final comments about you being governed by different(higher & better)standards and requirements in the US would be taken by many Canadians as offensive. My canine and I were trained and certified in the US but regardless of that, canines, flammable liquids and the laws of physics don't know or care which country they are in. However, from this Canadian I have found it is more important to be kind than to prove I am right. I hope this more clearly answers Mr. Norman's question.
05-04-2001, 04:32 AM #6SJNormanFirehouse.com Guest
Gentlemen, I thank you for your helpful responses thus far. In Australia at this time there is only one operational dog available and she is already involved in at least two PhD studies into her effectiveness and sensitivity (and I pass no judgement on here effectiveness because I know almost nothing about her). Since she is busy however I have intended to focus my detections on say GC/MS and other laboritory instrumentation. I was PARTICULARLY interested by the comment about foam causing a false positive. Can anyone expand on this? Who noted this and was it in a formal paper or simply some sort of oral comment? Thanx again guys.
05-04-2001, 10:00 AM #7CJBFireConsultantFirehouse.com Guest
I stated FACTS as to exactly what Dogs can and CANNOT do, according to US Law. Maybe Canada is different, I have no knowledge. But I would strongly suggest you read the LATEST articles from the US Dept of Justice, National Institute of Justice, as well as in the Fire & Arson Investigator from the International Association of Arson Investigators. There are MANY MYTHS about Dogs and their Capabilities, and these articles describe the EXACT problems faced with their capabilities and legal chalenges to those issues.
Don't kill the messenger..those are the FACTS.
05-04-2001, 10:13 AM #8CJBFireConsultantFirehouse.com Guest
On a separate issue, I would like to say I meant no offense at the previous postings. However, they were presented as informationals purposes and to be considered as WARNINGS to those who rely upon or use Cannines. Even if you may not agree with any of the information presented in those documents, I can tell you that an opposing attorney will probably have read them and cite them as basis for a legal challenge to the Cannine Issue.
I heard a quote once from a prominent attorney on CNN: "Knowledge is Power, Stay Informed".
So again, the intent of my postings was not to criticize you or your country. But it was to inform you of the latest WARNINGS by the US Dept of Justice and of successful recent legal challenges to the admissibility and use of cannines here in the US.
05-04-2001, 11:29 AM #9reyfordFirehouse.com Guest
Good morning Chris, those of us who are active fire investigators and who also use canines to assist us from time to time are pretty well up on the latest rulings and trends. We sort the good law from the bad law and try to anticipate how to handle those issues, should they arise. We are first and foremost scientific fire investigators, but I believe using all the tools that are out there allows me to provide a better service to my clients. As I stated earlier, most of the people trying to sway the population about canine use are not canine handlers and due to certain insecurities in their lives, for some reason feel threatened by anything different. My canine travels with me to all my fires. On occasions where she is needed, I use her. When she is not needed, due to the circumstances of the fire, I don't use her. I agree that knowledge is power, but as you know, much of the knowledge lawyers come to court with is not accurate knowledge. They even know that but will use it anyway. Therefore, it is incumbent on all of us in this field to be thoroughly aware of the real facts and be prepared to defend our knowledge in court. That way, some of the bad case law (and some of the erroneous articles) can be prevented before they become misinformation that hurts the industry.
05-04-2001, 09:40 PM #10SteamerFirehouse.com Guest
First of all, I apologize to Mr. Norman as my post doesn't address his question at all, but I read Mr. Bloom's comments with great interest. To Mr. Bloom, I have nothing but respect for you as you have always been nothing but professional, more than willing to share information.
I have read the editorial regarding the canines in the latest issue of the IAAI's magazine. I have also seen the website "discussions" become more of a p$*$&ng contest that borders on embarrasing for some of the people on both sides. To wade into that topic is an exercise in futility. I have found it has been better to agree to disagree on the subject and go on.
My question is regarding the issue of spilled gasoline being tracked and contaminating a fire scene being a dog issue. Specifically, why is that only a dog issue? It wouldn't be an issue if that area would have been localized by an electronic instrument, or an investigator who happened to notice the odor? To think that this is strictly an issue involving the use of canines is preposterous.
I guess I have more than one question now that I think about it. If the canines alert on foams used in firefighting (mine hasn't), I guess those that believe this is true would also have us believe that the chemists can't tell the difference either since every investigator I know sends their canine alert samples to a lab for examination. I'd be really interested in seeing the science behind that. (I'm really not being a smart-a%&...I really would like to see it.) Are the lab instruments as useless as the dogs are supposed to be? Surely the instrumentation used today can tell the difference between gasoline or kerosene and firefighting foams.
My canine and I are certified in the US through the Maine Criminal Justice Academy (he's a State Farm dog), and work in Ohio. I work really hard to keep my canine proficient using the recommended training methods. As I said, I've read the IAAI "guest editorial", and am aware of the arguments against the use of the canine. I won't even address the absurdity of the contents of that editorial. I know what I see with my dog and other handler's dogs and in spite of what you believe or don't believe, they are invaluable when properly utilized. Some simply don't like the canines being used, and we will never all agree on the issue. The bottom line is the investigator has to investigate the scene and not rely solely on the canine!
Again, Mr. Norman, I apologize for not offering anything substantive on your question, but I do know something about the arson canines. (I know...the word "arson" and canine shouldn't be used together according to some people. That's a topic I've seen debated ad nauseum as well.)
This is all my $0.02(US)worth. (My apologies Mr. Eyford; I just couldn't resist.)
Chillicothe (Ohio) Fire Department
[This message has been edited by Steamer (edited 05-04-2001).]
[This message has been edited by Steamer (edited 05-04-2001).]
05-06-2001, 08:49 PM #11eyecueFirehouse.com Guest
The type of foam that you need to be concerned about with false positives for accelerants is CLASS A. Obviously other foams would be used in the case of flammable liquid fires, whereas class A foam is used on ordinary combustibles. It has been years since I was involved in this information and I cannot recall where I saw it. You should consult the manufacturers of the product for more information. Sorry that I could not remember more. If you need further assistance you can Email me.
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