NFPA Journal

BY ANGELO VERZONI

When the citizens of Chicago rebuilt vast swaths of their city following the Great Chicago Fire of 1871, they swapped wood for brick and other noncombustible materials. Newspapers at the time lauded this new wave of construction as “fireproof.” 

Fifty years later, the city was reminded of the sobering truth. On March 15, 1922, flames rapidly tore through over a dozen buildings alongside the south branch of the Chicago River, causing an estimated $2.3 in losses—over $38 million in today’s money—and two deaths.

The Chicago Board of Underwriters published a report on the incident two months later. “There is no such thing as a fireproof building,” the report concluded. “It is absurd to expect that a building which is built partly of fire resisting materials and partly of combustible materials and filled with combustible contents will not be materially injured both as to structure and contents when subjected to high temperatures.”

The rapid fire spread was caused in part by industrial chemicals and waste present in almost all of the buildings involved in the fire. This included barrels of varnish and alcohol, wood and metal dust, gasoline, and other hazardous, combustible materials. “Floors were oil-soaked, premises were congested and heavily loaded, and there were many tenants using gasoline, making wood-working refuse, and having use for cleaning rags and waste,” the report found. The authors also speculated that the fire may have been sparked by the spontaneous combustion of oil-soaked rags in one of the properties. 

According to the University of Illinois Library, 80 percent of the entire Chicago Fire Department responded to the incident, fighting the fire for about four hours with 51 engine companies, six hook-and-ladder companies, seven squad companies, and two fireboats. As firefighters battled the flames, Chief Chicago Fire Marshal Thomas O’Connor reportedly remarked it was the worst blaze the city had seen since the citywide 1871 fire. One firefighter died at the scene while another, who was struck in the head by a falling piece of stone, died at the hospital later. 

The Chicago Board of Underwriters included in its report several recommendations for the city to protect against future large-scale incidents in the wake of the March 1922 conflagration. The recommendations primarily focused on making exterior openings like doors and windows more fire-resistant to prevent building-to-building fire spread, as well as decluttering and compartmentalizing interior spaces to prevent fire spread within the same building. “The idea must be,” the report said, “to bar out exposing fires and prevent lapping of interior fire from floor to floor.”