yeah BD , not unheard of , grain dust is very explosive in the right conditions ...
been a few good silo burns here in Oz over the years from the dust in elevators ..
and I've seen harvesters go up in seconds , but they are normally from bearings over heating to start it off ..
cheers
EDIT : Oh and dont you just hate newsdotcom after that reformat ...ABCnews getting a lot more of my time now
Haha ...