Airborne terrorism threat test includes releasing non-toxic gas into subway system

Non-toxic gas to be released into subway

The Department of Homeland Security will be releasing non-toxic gas into the subway system to imitate a biological and chemical attack.

NEW YORK - If you happen to see aerosol gases being pumped into the subway starting Monday do not be alarmed. It’s part of a nearly two-week-long study on airborne terrorism threats.

"This is not to signal to people there is an imminent threat," said former New York State Homeland Security Advisor Michael Balboni.

And this isn’t the first time researchers have released non-toxic particles and gases into the New York City subway system.

Several subway stations will be tested on five random days within the next two weeks.

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"The key here is if you believe your adversaries want to take down the core central transit system, then how would they do that? This would be one of those ways," said Balboni.

Balboni explains the particles and gases used in the study will imitate the movement of biological and chemical agents in a densely populated urban environment. Those gases will then be tracked, allowing researchers to understand the relationship between airflow on street level and in underground environments.

"This is just a proactive stance by MTA to ensure ppl are comfortable that airflow has been tested," said Balboni.