This from Larry Shapiro:

I was in the neighborhood when the 7th Battalion pulled up on a working fire in a three-story, brick apartment building at 3111 W. Diversey.   They had rear porches going with extension to a two-story house behind the building on Troy. He asked for a Box Alarm and companies made quick work of knocking down the fire. 

I arrived before the Box Alarm companies to find crews washing down hotspots. 

Chicago FD Truck 13

Larry Shapiro photo

Firefighters washing down rear porches after a fire

Larry Shapiro photo

Firefighters venting a roof during a fire

Larry Shapiro photo

Chicago FD Engine 91

Larry Shapiro photo

Chcoag FD Battalion 7

Larry Shapiro photo

Chicago FD mobile command board

Larry Shapiro photo

more photos at Shapirophotography.net