"I guess this is a personnel preference as to the use of the word undetermined. I still think the one word can lead to a misunderstanding. I also do not like using in my report negative words. I also do not want to have the perception that my answer is an absolute. The way I describe my finding is to say, “I presently do not have sufficient data to eliminate all potential possibilities as to the cause of this incident.” I will not argue that another person with different qualifications may be able to reach a conclusion."

Sufficient evidence or insufficient data and evidence. Not "insufficient data." You need evidence. Data is a necessary, but insufficient condition to reach a reliable determination using the SM.If the use of this term is contrary to NFPA 921, then one must justify your alternative use of the language.

"I feel undetermined is not sufficient because it does not explain why is undetermined. What were the reasons a conclusion could not be reached? During questioning some say that the reason for the undetermined was due to the fact their client did not want to pay for the work that was needed to reach a conclusion. It had nothing to do with there being insufficient data available to reach a conclusion. Other time the person did not have the knowledge to proceed further. If you just tell me the cause of the fire is undetermined, what are you trying to say. By using that one word there is not enough information for me to reach a conclusion as to the possibility of a conclusion being reached."

Your report should detail your application of the SM to a specific incident with the available data and evidence. The SM and reliable determinations should be reproducible or at the very least, based on differences in education, training, knowledge, and experience, provide an understanding of how the expert applied the SM to the specific incident. The reader can then understand why you arrived at an undetermined fire cause determination.

"The scientific method is reliable to a point. If any conclusion based on the use of the scientific method cannot be considered an absolute, then what is the degree of reliability? Here you are getting into a level of certainty. You state, “Without any evidence that allows one hypothesis to be uniquely consistent with the available evidence, any further determination beyond "undetermined," is subjective and unreliable.” The undetermined is the investigator’s personal opinion only. To say there cannot be a further determination is limited to the person making the statement but does not directly relate to others conducting the investigation."

"More probable than not."

It is the investigators "expert opinion" based on the reliable application of the SM to the available evidence to reach his/her determination.

Personal opinion, not based on the reliable application fo the SM, is both subjective and unreliable.

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