Susan Watts/New York Daily News

Subway riders have no need to panic over the gas — it’s only a test.

Don't hold your breath, it’s only a test.

The Department of Homeland Security will release “harmless particle materials” in the city’s subway system next week.

The “non-toxic, safe gas material” will be released at subway stations in Manhattan, Brooklyn, and Queens in order to understand where hazardous material would travel in the event of a biological terrorist attack.

NYPD INVESTIGATED THREE TERROR PLOTS LINKED TO ISIS

“This is important information to help local authorities to enhance their emergency preparedness,” DHS Program Manager Dr. Donald Bansleben said Friday.

Officials said there is currently no credible threat against either New York City or the subway system.

Poster Comment:

Trump gas? If they can lower their IQ a few more points, the majority might vote for Trump in the general election. After the first gassing in '13 they were dumbed down enough to give trump the GOP nomination.

And in 1950... Of Microbes and Mock Attacks: Years Ago, The Military Sprayed Germs on U.S. Cities