What is the ignition temperature of wood? NFPA 921 has for short term (less than one day) the minimum ignition temperature needed is approximately 482ºF (250ºC). There is a paper on the subject that reports smoldering ignition of wood was achieved within 30-minutes at the temperature of 298ºF (147.7ºC). When it comes to long term low temperature ignition, which based of NFPA 921 would be more than one day. There is little research into this area, however Vytenis Babrauskas reports that there was an actual case where it was verified that ignition occurred when wood members were exposed to heating sources at 77ºC (170ºF) or higher. He indicates that this forms a reliable, scientific basis for concluding that an ignition hazard exists if a heat source at 77ºC or higher is applied to a wood member for a protracted period of time. He does not report the amount of time necessary. It is known that steam pips passing through and in contact with wood will ignite at 212ºF (100ºC).

Does anyone have additional thoughts on this topic.

Jim Mazerat
Forensic Investigations Group