In response to the terrorist attacks of September 11, a new report, "Risk Management Guidance for Health and Safety Under Extraordinary Incidents," has been released by the American Society of Heating, Refrigerating and Air-Conditioning Engineers.

Most of the recommendations are common sense measures that building owners and managers should already be following, said ASHRAE President William Coad, PE.

While more resources may be spent now to enhance building performance and reduce risks to occupants from extraordinary incidents, the report cautions building owners and occupants to:

  • Understand the capabilities of buildings and their systems;
  • Assure that buildings are performing as intended;
  • Make no changes to building performance unless the consequences are understood.

Building performance-related systems, components and processes that could affect safety include ventilation system operation, filter efficiency and bypass, quantity of outdoor air, controlled access to air handling components, securing of likely entry points, fire protection and life safety, building shell and duct tightness, areas of refuge and preparedness planning.

According to the report, professional engineers should be consulted before:

  • Closing outdoor air intake dampers or otherwise blocking ventilation air paths;
  • Changing the designed airflow pattern or quantities;
  • Modifying fire protection and life-safety systems without approval of the local fire marshal.

A copy of the report is available at