Sawdust fires can indeed be hard to fight. First you are dealing with a very combustible product. Second it is conveyed to a dust collector with all the ingredients for a fire and deflagration. All that is needed is a spark to complete the Fire Triangle. As per NFPA 664, a listed Spark Detection & Extinguishing System in the conveying system is a very effective tool in preventing this type of fire. Third, saw dust is typically stored in a silo or bin with enough volume that it is hard to extinguish any embedded embers or fires not matter how good your sprinkler or deluge system, because the water will tunnel through the material instead of wetting it thoroughly and consistently. And fourth, with enough combustible dust disbursed within the vessel, as you empty it you create an increasingly explosive atmosphere . Firefighters are at risk of injury when opening a dust collector or storage vessel as they are adding oxygen to a combustible dust cloud with an embedded ember.
|Sawdust Fire Proves Difficult to Extinguish in Ind.|
Firehouse.com (subscription) - USA
... Chief Dave Huff said he was unsure what ignited the highly combustible material. ... Also, a cable holding up the dust collector unit, or baghouse, ...