A collision of two small private planes over Zion, Ill., on Feb. 8, 2000 sent one of them crashing onto the roof of the 95-bed Midwestern Regional Medical Center.
The impact created an 8-sq.-ft. hole in the roof, and sheared one structural beam, causing it to drop by 3 feet. Moments later, the plane exploded in flames, knocking down all walls on the medical center's 8,000-sq.-ft. fifth floor and bowing exterior walls outward as much as 10 degrees.
The physical damage was apparent, but the more significant implications were largely not realized initially. A sprinkler main ruptured by the crash allowed water to pour onto lower floors. Concerned about the possibility of additional explosions, the city requested that the sprinklers not be shut off until the hospital was completely evacuated, hours later. All patients were moved to alternate medical nearby facilities.
Because moisture promotes the growth of mold and bacteria, even walls with no apparent visual damage had to be replaced. The adhesive used on wall panels that bonds gypsum to the panels' outer paper layer is organic and could support spore/mold growth, according to Michael Arenson, a principal with Northbrook, Ill.-based SAS Architects & Planners. His firm, which was architect for the remedial work, was also the original architect for the building, which was completed in 1990.
Michael White, medical center administrator, said more than $170,000 was spent on air quality testing, which included taking petri dish samples from wall surfaces. Higher-capacity filters also were installed in HVAC ducts. Project team members worked with the Illinois Department of Public Health to eradicate mold, or the opportunity for it to develop.
The cost of remedial work exceeded $5 million, and the environmental-related portion was at least five times more costly than the repair of physical damage, Aronson says.
Patients began moving back into the hospital seven days after the accident, and reoccupancy was completed four weeks later. Building repairs took six months. The general contractor for the cleanup and the reconstruction was Waukegan, Ill.-based Car-Min Construction Co.
Widespread media coverage of the accident was in part because the plane that crashed onto the roof was owned by Chicago radio personality Bob Collins. He was killed, along with two others - a passenger in his plane and the pilot of the other aircraft.