"Yes, I did not address the specific fuel. I guess I should not have taken it for granted that the fuel source was identified. So, let’s say the first fuel ignited was identified. Now I am attempting to identify the source of energy that ignited this fuel. I cannot address what brought the fuel and the source of ignition together until I identify the ignition source. Not identifying the source of ignition, I still know from other evidence that this was the fuel first ignited. Since I know the fuel, I hypothesize that three was a component source of ignition, even though I could not identify it. I saw the fuel being ignited. I know the fuel’s location. I know this fuel will not self-ignite. I have evaluated all the potential ignition source present. I cannot say which of the potential source of ignition in that area was the one that ignited the fuel."

If you have multiple competent ignition sources for the same fuel, then you have multiple fire cause hypotheses. If you do not have a fire cause hypothesis that is uniquely consistent with the available evidence, your fire cause hypothesis is "undetermined."

"My deductive reasoning is, I know the fuel ignited because I observed it being ignited. I know the location of this fuel. Using deductive reasoning I have evaluated each of the potential sources but cannot say to any certainty which was the source of ignition. Using deductive reasoning I have determined that one of these sources had to be responsible for ignition. My hypothesis is that the fuel was ignited by one of the ignition sources, but it is not possible to say which one. So I say for ignition of this fuel to have taken place, the fuel was ignited by a unidentified component ignition source. Is my hypothesis that this fuel was ignited by a component ignition source valid?"

I am not sure I understand your point of this example. This is not a fire cause hypothesis, where you have identified each element of the fire cause with evidence in this specific incident. What you have done is really define what a fire cause is.

Douglas J. Carpenter, MScFPE, CFEI, PE, FSFPE
Vice President & Principal Engineer
Combustion Science & Engineering, Inc.
8940 Old Annapolis Road, Suite L
Columbia, MD 21045
(410) 884-3266
(410) 884-3267 (fax)
www.csefire.com