Station 21 dispatched for a outbuilding  on fire. Engine 211 enroute with 3. Safety Officer 2110 arrived on scene advised that it was a 10'x10' outbuilding on the ground fully involved. Engine 211 arrived on scene pulled a 1 3/4 line. Chief 2101 took command and told C-com that engine 211 could handle. Captain 2105 with firefighter 2125 and 2122 extinguished the fire.