In addition to all the other exotic fumes roiling around the subway, the NYPD will this summer release some nice, "harmless" gases into several stations in order to test for "risks posed by airborne contaminants, including chemical, biological and radiological (CBR) weapons," the department announced today.

“The NYPD works for the best but plans for the worst when it comes to potentially catastrophic attacks such as ones employing radiological contaminants or weaponized anthrax,” Police Commissioner Raymond W. Kelly said in a statement. The airflow tests will be performed in partnership with the energy department's Brookhaven National Laboratory using perfluorocarbon tracer gases (PFTs), which, though alarmingly named, are apparently benign. (Wikipedia tells us the gases are regularly used to map oil reserves and, awesomely, to track ransom money following kidnappings.)

The $3.4 million study, called the Subway-Surface Air Flow Exchange, will be the largest of its kind. The exact dates of the test, to be held over the course of three non-consecutive days in July, will be determined by weather conditions and announced to the public one day in advance. Research will be conducted during the daytime in parts of all five boroughs, but is not expected to hamper operations.

“The NYPD, in partnership with the MTA, is responsible for keeping more than 5 million daily subway customers safe and secure, Acting Chairman Fernando Ferrer said in a statement. "This study will bolster the NYPD's understanding of contaminant dispersion within the subway system as well as between the subway system and the street, thereby improving its ability to better protect both our customers and the city population at large."

Sounds good, Ferrer. Now when will someone look into the MTA's little electric eel problem?