"This comprehensive plan meets the shared commitment on the part of CNA and the City of Chicago to ensure public safety," said Bernard Hengesbaugh, chairman and CEO of CNA. "The film system we have already installed provides the strongest protection against glass fallout while we systematically replace our windows with the best technology available."

    In consultation with the City of Chicago Department of Buildings, CNA commissioned a critical investigation of the building's facade by the engineering firm of Wiss, Janney, Elstner Associates (WJE) following the fallout of a piece of glass from the building in October 1999. Mrs. Ana Flores of Chicago died in that accident.

    Upon completion of an exhaustive 11-month critical investigation, WJE established that the window glass currently used in CNA's South Tower is subject to thermal stress, which can cause windows to crack under certain light and temperature conditions. As a result, CNA will install heat-strengthened laminated glass, which is recognized by experts as the best glass technology in existence to address thermal stress.

    In addition to undergoing heat-strengthening during the manufacturing process, the glass contains a built-in safety film to prevent glass fallout. On four floors where computer equipment requires special insulation, CNA has installed heat-strengthened insulated glass units equipped with the 3M anchored-film restraint system. All windows being installed at CNA meet or exceed established national standards for glass strength and glass design published by the American Society for Testing and Materials and the American Society of Civil Engineers.

    Notwithstanding the replacement of windows in the South Tower of CNA Plaza, CNA will maintain its window inspection program.

Related Story: CNA Settles Lawsuit [Dec. 2000]