Sparks from a grinding operation are the suspected culprit in a fire that ignited in two connected sawdust bins at Boise Cascade in Medford Tuesday morning, prompting a five-engine response from two agencies.
About 18 firefighters from Jackson County Fire District No. 3 and Medford Fire-Rescue responded to the blaze at 3285 N. Pacific Highway at about 11:40 a.m. Crews stayed on scene for about four hours, mopping up hot spots and pouring extra water onto the sawdust and bins.
"Really the initial knockdown happened with the automatic sprinkler system," said Arlen Blenkush, District No. 3 battalion chief.
Crews originally thought the fire might have been caused by a hot wood chip that got sucked into one of the bins, but further investigation suggested sparks from a nearby grinding operation on-site could have been the catalyst.
The fire was contained to the inside of the bins and did not damage the structure's exterior.
Crews removed the sawdust from the bins a little at a time and poured extra water on it to make sure no embers remained. It's a delicate operation, as removing too much dust too quickly can result in abrupt flare-ups because of the added oxygen.
"It's in such a fine particulate matter that it can literally do what we call a low-grade explosion," said Hugh Holden, District 3 fire marshal.
The removal and extinguishing operation went smoothly.
"It was very, very uneventful, which is the way we like it," Blenkush said.
Leaving the sawdust in the bins would require crews to fill them up with water to fully extinguish the embers, which could be a problem for the structure because of the added weight.
"You can literally hear the structure starting to groan under the weight," Holden said.
Boise Cascade officials said numerous safety measures are in place in case such a fire occurs. If a smoldering wood chip makes it into one of the bins, sensors shut off the flow of sawdust to make sure no additional dust or small chips get in.
Reach reporter Ryan Pfeil at 541-776-4468 or by email at firstname.lastname@example.org.