NYC will test 'gases' in their subway systems

[nodle]

Ya I am sure this is just a 'test' and all 'safe'.

The MTA and the Department of Homeland Security are conducting a somewhat ghoulish experiment this month.
On five days between October 18 and 29, they'll be releasing non-toxic gas at about 120 subway stations to test NYC's response plans for a chemical or biological attack, according to the New York Daily News.

NYC subway stations will be pumped with non-toxic gas this month (timeout.com)