The NYPD’s Subway Gas Experiment Begins Monday

Photo: Joe Raedle/2011 Getty Images

Remember that practice subway gas attack the NYPD was planning for this month? Well, the first day of that is tomorrow, when they'll pump an odorless, colorless, nonreactive gas into the tunnels to see how the air flows down there, and what a chemical leak or gas attack might look like. From the way the city is describing this, riders won't even be able to tell they're doing it; but if someone does start freaking out, remember that this is just a test.