Vyto has postulated a hypothesis that the cycle of heating of the wood and cooling of the wood allows water condensation on the surface of the wood. This contact then would change the chemistry of the wood to a point that it would lower the ignition temperature. While he provides some evidence that this has the potential to occur, this hypothesis has not been tested.

Vyto provides this in the Ignition Handbook. He bases this on a reference of past work. I would have to go back and review this reference, but I remember being some conditions of the work that may have not been "substantially similar" to the conditions of interest.

Douglas J. Carpenter, MScFPE, CFEI, PE, FSFPE
Vice President & Principal Engineer
Combustion Science & Engineering, Inc.
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