Not surprisingly, the construction industry's response to terrorism was a prominent theme at the Associated General Contractors of America's annual convention in Las Vegas last month. No fewer than seven sessions of the four-day program related directly to Sept. 11 and subsequent developments.
Speakers described moves made by the military services and attempted to predict how these developments might affect the design and construction of nonmilitary buildings. The sessions included presentations by three representatives of the U.S. Army Corps of Engineers — Dwight Beranek, chief of its engineering and construction division; Curt Betts, security engineer with its Protective Design Center; and Robert Hall, chief of its geosciences and structures division.
Of note, Beranek said the number of military facilities defined as "critical" has been increased. This more intense analysis began during the Clinton Administration with an emphasis that extends beyond facilities themselves to the infrastructure around them. He said an additional $50 million to $100 million a year will be spent on civil construction for upgraded security, focused primarily on access control.
Tighter security-related contracting policies will decrease the number of contractors and construction workers who qualify to perform such work, according to Beranek. It also may be necessary to restrict the dissemination of project information only to contractors with valid contracts, he said.
Beranek noted the formation of the Infrastructure Security Partnership, which was organized to facilitate information sharing with respect to security-related building standards development. More than 60 organizations have committed to join, and Beranek will be the group's first chairman. The American Society of Civil Engineers has established a Web site, www.tisp.org , to facilitate an exchange of information.
Betts described the minimum antiterrorist standards applicable to all inhabited Department of Defense (DOD) building projects, which cover new construction and renovations whose cost exceeds 50 percent of the building's existing value. They will also apply to leased buildings in which DOD personnel occupy at least 25 percent of the space.
He also observed that an adequate standoff zone is generally the most cost-effective option for increasing security. "With a perimeter of 150 feet, you can pretty much use conventional construction," Betts said. Additional security features for buildings on tight urban sites could increase construction costs as much as 20 percent, he added.
Structural analyst Hall said security-related research by the military is focused primarily on preventing structural collapse and flying debris following the detonation of an explosive device. He noted that the plane that crashed into the Pentagon hit both renovated and unrenovated sections. Hall showed pictures of blown-out windows 100 feet from the point of impact in the unrenovated section, and undamaged laminated glass windows 55 feet from the point of impact in the renovated portion (for more on the Pentagon, see page 40).
Bob Silver, assistant director of the Naval Facilities Engineering Command's engineer operations center, said new antiterrorist measures include the placement of air intakes above the first floor, an emergency shutoff of HVAC systems to prevent the dispersion of biochemical agents, placement of mailrooms at the building perimeter and the use of laminated glass. "We need to move from mitigating fear to mitigating risk," Silver said.
Other topics addressed at the convention included a concern that mold growth in buildings is becoming a serious problem. John Kelly, executive vice president of Minneapolis-based developer Ryan Companies, characterized it as "the next issue to reach the level of indoor air quality and ADA regulations."