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Re: Undetermined Accidental?
Posted by:
dcarpenter (IP Logged)
Date: January 31, 2007 01:03PM
Based on the 2004 edition of NFPA 921, Section 18.6 and your use of "probable" with respect to the only two remaining hypotheses, I would offer the opinion that you would have to conclude at this point that it was at least an undetermined cause, assuming a valid origin determination.
The question of accidential or intensional for me is alway more difficult to specifically answer. I have always had a hard time with the concept of an accidential or inceniary fire detemination for an undetermined origin and/or cause. If you take the approach (as I do as well as many others) that a fire is always determined to be accidental unless proven otherwise (i.e. a presumption that the fire is not incendiary). So if there is no evidence to overcome the presumtion of an accidental fire, then it should be classified as accidential. This determination may require some additional clarification such as an assignment of the level of confidence (i.e. possible or probable) or a qualifer such as "based on no evidence to-date of an incediary fire."
Additionally, if you assume that all the available evidence has been collected, the origin of the fire is technically sound and all the available data has been used to test the hypohteses within the scientific method and that these two cause hypotheses are the only two cause that can not be eliminated, then it may be reasonable to determine the fire as accidential in this case. A determination in this specific case does require that these assumptions are valid.
Furthermore, if all the available data has not been used to test all of the hypohteses related to origin and cause, then again, this supports an undetermined origin and/or cause. In your description, there was a determination of no "foul play" based on an autopsy, which I have to assume, based on the limited data, means that there was uptake of products of combustion and no obvious trauma. There is still the potential of obtaining valuable information that can be used to test an origin and cause hypothesis contained within any tox screen. So again, this supports an unddetermined fire.
I see no logical reason not to use accidental and undetermined. There may be reasons otherwise why such a determination can not be used within certian organizational reporting requirements.
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