Metalized film capacitors as fire pattern

NFPA921 defines a fire pattern as a pattern that remains after a fire as a result of a fire. Beyond arc fault mapping, very little investigation has been reported on patterns caused by failures within electrical devices, or patterns that result in electrical devices that are attacked by fire. Electrical arc beads are of interest in fire investigations because they can persist after the fire has been suppressed and they can be used to supplement other fire patterns. Investigators would likely find it useful to know whether other electrical or electronic components (other than copper wire) produce and retain fire patterns that indicate whether they were energized when attacked by the fire.