Engine 412 along with several other units in Baltimore County were alerted for a barn fire early this afternoon. E412 arrived and helped setup water supply as there were multiple engines already at the barn. E412 supplied water it received from Carroll County units. Once the fire was suppressed E412 was requested to go down to the location in order to use foam to completely cover what was left of the barn. Foam enables the water to soak into the burning material which cools and reduces access to oxygen. Units cleared around 4:30pm.