Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires

Living Edition
| Editors: Samuel L. Manzello

Hot Metal Particles

  • Vytenis Babrauskas
Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-51727-8_2-1


Sparks. The term “spark” can refer to either a non-sustained electrical discharge or a small, airborne, incandescent body. In the latter meaning, “hot metal particles” and “sparks” are synonyms.


Hot metal particles considered in this section are small (a few millimeters or less) particles which are ejected from some process while heated to an incandescent state and can potentially act as ignition sources for a fuel.

Grinding sparks are hot metal particles created by a grinding operation.

Impact sparks are hot metal particles created due to a high-speed collision of two hard objects.


A common cause for ignition of wildland fires are hot metal particles. These can come from numerous sources or activities (Babrauskas 2003; Mitchell 2009):
  • Railroads

  • Electric power lines (from conductor clashing, broken insulators, downed conductors, etc.)

  • Welding or torch-cutting metals

  • Grinding

  • Impact of power tools

Ignition of vegetation may be smoldering or flaming, but...

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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Fire Science and Technology Inc., and Department of Mechanical and Aerospace EngineeringUniversity of CaliforniaSan DiegoUSA

Section editors and affiliations

  • Sayaka Suzuki
    • 1
  1. 1.National Research Institute of Fire and Disaster (NRIFD)TokyoJapan