Cook County Administration Building

Chicago, IL

Market: Office


Cook County Administration Building fire
malfunctioning smoke louvers
malfunctioning smoke louvers

On the afternoon of 17 October 2003, a fire started on the twelfth floor of the thirty-seven story Cook County Administration Building.  At that time, the doors from the stairway to the vestibules on most of the floors were locked against exiting from the stairway.  Six people found in the southeast stairway above the fire floor had died of smoke inhalation.  SGH evaluated the impact of malfunctioning smoke louvers that were part of the smokeproof enclosure system for the exit stairway, and provided expert opinions on the conditions that led to the fatalities as a result of the fire.

Scope | Solutions

SGH gathered information related to this event by documenting the fire damage and building features.  We also reviewed relevant witness testimonies, reports, video footage, photographs, drawings and other construction documents, and applicable codes and standards.

SGH performed computational fluid dynamics (CFD) modeling using the National Institute of Standards and Technology’s (NIST) Fire Dynamics Simulator (FDS) software to quantify the impact of a properly-operating smoke louver in the southeast stairway of the twelfth floor.  We used modeling to simulate the smoke and heat transport within the floor of origin and into the stairwell where the occupants were trapped, demonstrating the difference in carbon monoxide levels between the actual scenario (louvers closed) and an ideal design scenario in which the smoke stacks vent the smoke and toxic fire by-products.  As part of a confidence testing procedure used to justify the plausibility of the results, SGH developed thirty-two CFD models in order to test the sensitivity of inputs. 

Based on our studies, we determined that the occupants most likely would have survived if the louvers had functioned as intended.