At 0714 hours, units were dispatched to 118 Mallard Lane in La Plata for the House on Fire. Engine 102 responded as the 2nd due engine company. E102 arrived and established a secondary water supply to the fire ground. E102 was assigned to RIT duties with Engine 121(Westlake). Moments later a MAYDAY was called as 2 firefighters fell through the floor, but was quickly cleared, as the firefighters were able to self rescue and exit the structure. Crews battled this fire for over 30 minutes, dealing with extension, as well as holes in the floor. E102 cleared shortly after 0900 hours. Both firefighters are home and doing well.