Boston Subways to undergo gas tests
A team of scientists plans to release nontoxic gases and particles into Boston's subway tunnels to study how they could spread through the nation's oldest subway system in a terror attack.
The weeklong study is commissioned by the U.S. Department of Homeland Security to figure out ways to quickly minimize the impact of an airborne assault on the nation's 15 subway systems.
Officials say the airflow tests starting on Friday will help protect the nation's critical infrastructure. U.S. subway systems include 810 miles of track in tunnels.
The U.S. is still wrestling with how to combat terrorist threats to its subways nearly nine years after the Sept. 11, 2001 attacks.
Authorities thwarted an al-Qaida-sponsored plot to attack New York City subways last September.
