Like a scene from a horror or crime film, an invisible, odorless gas will be released into seven subways throughout New York City this July. But this gas will be harmless, part of a controlled experiment conducted by New York City police and Brookhaven National Laboratory to better understand how particles circulated in the subway’s underground air, the New York Times reports.
The gases, known as perfluorocarbons, will be dispersed to study how airborne toxins would flow through the city after a terrorist attack or an accidental spill of hazardous chemicals, the department said on Wednesday.
Around 200 monitors will trace the gases’ path, in the biggest study to date on measuring and understanding urban airflow. The police are especially interested in how the subway system influences the flow of air above ground. Knowing this would help authorities decide which trains would need to shut down in the event of an anthrax attack or hazardous radioactive spill, for example. Likewise, toxic gas released above ground could infiltrate some tunnels below ground and endanger subway riders.
Mr. Kalb said his colleagues planned to enlist about 100 college students as interns to help set up the test and gather air samples to be analyzed. He said they would install small black-and-gray boxes containing monitoring equipment on subway platforms and lamp posts poles around the city. Then, the traceable gases will be released in seven different locations — three above ground and four below — on three nonconsecutive days in July.
In order not to spook the public, the police plan to issue prior announcements about the experiment as well as list numbers and web addresses that concerned citizens can reach out to for more information.
But you have the think that plenty of nasty toxins may already be lurking in the dank subway system. Rest assured, a new study says. Researchers found that microbes in the air in the NYC subways and those floating around above ground air were nearly identical. That’s not exactly reassuring, but it does mean that there likely are no super bugs lurking in the air near the tracks or on the train. The only slight variation the researchers found was a slightly higher density of skin microbes and fungal microbes, which may come from rotting wood.
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