Perhaps the most critical pieces of advice offered by mechanical engineers to building owners and managers fearful of attacks on their properties is what not to do, rather than what to do. Beware of opportunists: "Do not close outdoor air intake dampers or otherwise block ventilation paths; do not change the designed airflow patterns or quantities; and do not modify the fire protection and life safety systems without approval of the local fire marshal."
So says the American Society of Heating, Refrigerating and Air-Conditioning Engineers Inc. in an eight-page "initial" report issued last week. Risk Management Guidance for Health and Safety Under Extraordinary Incidents also offers guidance on steps that can be taken to render buildings somewhat less vulnerable to bioterrorism and other attacks. But for the time being, unless the building is an obvious target, ASHRAE recommends operating buildings normally and, in every case, not making any changes without consulting a professional engineer or system expert. "We have to take time to figure out if [owners] need to do anything different to operate their buildings as safely as possible in the event of another incident," said William J. Coad, ASHRAE president, at the Jan. 12-16 winter meeting in Atlantic City, N.J.