On April 22 at approximately 8:12 pm, the First Alarm Assignment was dispatched to assist the Downingtown Fire Department on a building fire at the STEM Academy in the Borough of Downingtown. Crews arrived to find a smoke condition in the building with a sprinkler activation. After the first interior crew entered the structure, it was determined there had been a small fire that was extinguished by the sprinkler system and contained to a ventilation hood system. Crews remained on scene as the fire room was determined to be a chem lab and it was unknown what chemicals were involved. The Chester County HAZ MAT Team arrived and entered the structure to determine the chemicals were somewhat common and that crews could continue the cleanup and overhaul safely. WBFC crews were initially assigned to assist with de-con, accountability and a final check of the second floor for fire extension and smoke conditions. Crews cleared shortly after 11:30.