This morning marked the beginning of the NYPD and Brookhaven National Laboratory's collaborative efforts to analyze how chemical weapons could travel through air. This of course means releasing harmless gases throughout the subway system. 

Earlier today, NYPD officers were spotted dropping air-sampling devices in designated places within the subway and on the street throughout the city's five boroughs. Researchers will use gases, known as "perfluorocarbons," which travel in the same fashion as a biological or chemical weapon would if it were released. 

This initiative, which was announced back in April, is being funded by a $3.4 million grant. According to NYPD Commissioner Ray Kelly, the results will aid the police force in understanding how toxic chemicals move underground, specifically near subway entrances and exits. 

If your train was delayed this morning, it's because the city is taking precautions to make sure it's better equipped to handle potential threats to keep you safe.

[via NBC New York]