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DHS S&T Releases Draft Environmental Assessment on Proposed NYC Subway Airflow Study

Release Date: March 8, 2016

For Immediate Release
DHS Science & Technology Press Office
Contact: John Verrico, (202) 254-2385

WASHINGTON— The Department of Homeland Security (DHS) Science and Technology Directorate (S&T) today released for public comment a Draft Environmental Assessment (DEA) and proposed Finding of No Significant Impact (FONSI) on the use of non-toxic, inert, odorless gas and particle tracers for experiments in portions of the New York City subway system.

The objective of the May 2016 airflow study is to gather data on the hypothetical behavior of airborne contaminants in the event they were released into the subway system. These tests will use only inert gas and particle tracers that pose no risk to the general public or the environment.

“This study is part of the Department’s ongoing commitment to preparedness and the shared responsibility of protecting the nation’s critical infrastructure,” said DHS S&T Program Manager Dr. Donald Bansleben. “While the deliberate release of chemical or biological agents is our primary concern, the results from these tests will also help researchers understand airflow characteristics for smoke or unintentional spills of chemicals or fuels and aid NYC emergency managers in the development of evacuation, ventilation, and other incident-response strategies. The information will also contribute to the design of next-generation chemical and biological agent detection systems.”

“The Metropolitan Transportation Authority continues to be an active partner safeguarding the New York City subway system and this study will generate valuable information on protecting against airborne contaminants,” MTA Chairman and CEO Thomas F. Prendergast said.  “These inert gases are safe for our customers and employees, and the entire test will be performed with no impact on them and no interruption to service.  We are fully committed to keeping our nearly six million daily subway customers safe and secure, and this test will bolster the MTA and our partners’ ability to protect them and the city at large."

The study will be conducted by researchers from several government laboratories, and will use perfluorocarbon gas tracers, which are harmless, non-toxic inert gases that have been used in dispersion experiments since the 1960s. Inert particle tracers consisting of the simple sugar maltodextrin and silica will also be used. These tracers are tagged with synthetic, non-infectious DNA fragments as well as a common optical brightener commonly in laundry detergents and paper manufacturing. These non-biologically derived materials will allow detection at very low concentrations.

The DEA and FONSI on the use of these materials can be downloaded from the DHS Web Site:  http://www.dhs.gov/national-environmental-policy-act and comments may be submitted until April 6, 2016 to: mtanycttest@hq.dhs.gov.


Last Updated: 01/12/2021
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