Elevator Explosions
Given a large enough suspension of combustible flour or grain dust in the air, a significant explosion can occur. A famous historical example of the destructive power of grain explosions is the 1878 explosion of the Washburn "A" Mill in Minneapolis, Minnesota, which killed eighteen, leveled two nearby mills, damaged many others and caused a destructive fire that gutted much of the nearby milling district. (The Washburn "A" mill was later rebuilt and continued to be used until it was shut down in 1965.) Another example occurred in 1998, when the DeBruce grain elevator in Wichita, Kansas exploded and killed seven people. The most recent example is an explosion on October 29, 2011 at the Bartlett Grain Company in Atchison, Kansas. The death toll was 6 people. Two more men received severe burns, but the remaining four were not hurt.
Almost any finely-divided organic substance becomes an explosive material when dispersed as an air suspension; hence, a very fine flour is dangerously explosive in air suspension. This poses a significant risk when milling grain to produce flour, so mills go to great lengths to remove sources of sparks. These measures include carefully sifting the grain before it is milled or ground to remove stones which could strike sparks from the millstones, and the use of magnets to remove metallic debris able to strike sparks.
The earliest recorded flour explosion took place in an Italian mill in 1785, but there have been many since. The following two references give numbers of recorded flour and dust explosions in the USA in 1994 and 1997. In the ten year period up to and including 1997, there were 129 explosions.
Read more about this topic: Grain Elevator
Famous quotes containing the words elevator and/or explosions:
“The cigar-box which the European calls a “lift” needs but to be compared with our elevators to be appreciated. The lift stops to reflect between floors. That is all right in a hearse, but not in elevators. The American elevator acts like the man’s patent purge—it works”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“Our Lamaze instructor . . . assured our class . . . that our cervix muscles would become “naturally numb” as they swelled and stretched, and deep breathing would turn the final explosions of pain into “manageable discomfort.” This descriptions turned out to be as accurate as, say a steward advising passengers aboard the Titanic to prepare for a brisk but bracing swim.”
—Mary Kay Blakely (20th century)