research project details
Project Title: Countering Terrorists’ Use of HVAC Cooling Towers as Delivery Systems for Biological and Chemical Agents
Investigator(s): Jack Matson, Jay Regan
Sponsor:US Civilian Research and Development Fund Foundation
Research project summarized by student intern Ruth Gilbert
Environmental Problem Addressed:
Dispersal of biological and chemical warfare agents via aerosol drift from cooling towers.
Research Project Objectives:
To compile information for a guidance document providing a multi-barrier protection strategy against usage of cooling towers by terrorists. Specific objectives include:
- Development of new technology for reducing drift emissions;
- Use of models to predict the impact and exposure of aerosol deposition;
- Evaluation of operation and maintenance practices that will limit the persistence of biological agents in cooling towers; and
- Investigation of sensor technologies to detect hazardous agents in cooling towers.
Summary:
Since the attacks of September 11, 2001 and the following Anthrax attacks, there is a heightened consciousness regarding the threat that chemical and biological agents represent to our national security. Cooling towers, used for air conditioning in heavily trafficked commercial centers (added to explain the use of cooling towers), number approximately two hundred fifty thousand (added to give magnitude of problem) in the United States. Cooling system water is lost by carry over of droplets as drift in the exhaust air stream. This drift contains visible droplets, as well as aerosol that can be inhaled and could provide a potential delivery system for biological and chemical agents dispersed by terrorists.
This research will investigate and develop a multi-barrier strategy to safeguard civilians from this potential terrorism threat. The project focuses on 5 specific elements:
- Drift Reduction System: the focus of this element is the removal of fine aerosols from the drift
- Operations and Maintenance Procedures
- Sensor Technology
- Impact and Exposure Modeling
- System Integration
To prevent this, several elements need to be investigated. First, determining a way to reduce drift from cooling towers can decrease the risk of biological or chemical agents being spread. Second, operations and maintenance procedures should be developed to inhibit microbial growth and inactivate introduced pathogens. Next, sensors should be put into place to detect foreign chemical agents. To attain the information needed to develop these elements, models will be used. Finally, the different elements can be integrated to create a multi-barrier strategy for the protection of cooling towers from potential use by terrorists.
Research will result in a report providing technologies and methods for minimizing the threat of use of cooling towers by terrorists.