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  1. Science and Technology Directorate
  2. News Room
  3. News Release: S&T, MTA and MIT Test Virus Mitigation Measures to Protect Riders on Public Transit

News Release: DHS S&T, MTA and MIT Test Virus Mitigation Measures to Protect Riders on Public Transit

Release Date: December 15, 2020

S&T Public Affairs, 202-254-2385

WASHINGTON – In its ongoing effort to combat the global COVID-19 pandemic, the Department of Homeland Security (DHS) Science and Technology Directorate (S&T), in partnership with the New York Metropolitan Transportation Authority (MTA) and Massachusetts Institute of Technology Lincoln Laboratory, will conduct tests in a real-world environment to determine the most effective measures to reduce the spread of viruses on public transit.

The MTA is the largest public transit system in North America, operating New York’s subways, buses and paratransit services, two commuter rail lines, and nine tolled bridges and tunnels. The system served nearly 9 million daily customers across 5,000-square-miles, prior to the COVID crisis. These tests will provide MTA and transit authorities across the nation with actionable evidence to further protect the health of passengers and workers who rely on these types of vital public transportation. The joint tests consist of dispersing a safe, aerosolized water-based solution in out-of-service buses, subway and rail cars in a manner that mimics a human breathing, talking, coughing or sneezing. Researchers will utilize various detection, quantification and modeling methods to investigate multiple factors, including:

  • Accumulation and Spread: Concentration in HVAC filters, cloth coupons, air sampler filters, skin wipes, face masks, etc.
  • Simple Mitigation Methods: Window operation, door operation, modifying HVAC settings, modifying air filter types, and wearing masks.

The tests will be conducted over the course of a week from late January to early February 2021 at several transit sites in New York City. The public will not observe or participate in these tests, which will occur outside of peak operating hours. When testing is complete, vehicle interiors will be cleaned before returning to service.

A Draft Environmental Assessment has been prepared in accordance with the National Environmental Policy Act of 1969 (NEPA) 42 United States Code (USC) 4321 et seq., the President’s Council on Environmental Quality (CEQ) Regulations Implementing the Procedural Provisions of NEPA (CFR § 1500-1508), and DHS implementing regulations.  Public comments are welcome and may be submitted to: mta-nyc-test@hq.dhs.gov. DHS S&T will review all comments received by the close of business on January 15, 2021.

In response to COVID-19, DHS S&T has focused its efforts on research and providing valuable resources to inform the fight. S&T summarizes scientific research from around the world in the Master Questions List, consolidating what is known about the virus and what additional information is still needed. S&T has also produced calculators that determine the lifespan of the virus on surfaces and in the air under varied environmental conditions. Additional highlights of S&T’s response can be found in our Battling the Invisible Enemy report.

The MTA’s ongoing efforts include a mask mandate, overnight cleaning and disinfecting program, an app to monitor capacity for social distancing, and vending machines that sell personal protective equipment. It is also piloting technology to filter and purify air inside rail cars using an electrical field to generate a wave of ionized particles that destroy airborne viruses, bacteria and particulate matter, including COVID-19.


Last Updated: 04/01/2024
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