An open fuel tank sign sits outside the fuel cell hangar at Hurlburt Field, Fla., Feb. 21, 2014. During open tank maintenance, the area is cordoned off to create a controlled area free of spark producing and 
<p>non-intrinsically safe equipment.(U.S. Air Force Photo/Staff Sgt. John Bainter)
</p>
<br>Unit: Air Force Public Affairs Agency
Staff Sgt. John Bainter
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