Researchers from the Brookhaven National Laboratory on Long Island recently completed the second phase of their three-phase Subway-Surface Air Flow Exchange (S-SAFE) study on Friday morning, conducting air sampling throughout the five boroughs
The $3.4 million project was funded through a Transit Security Grant from the Department of Homeland Security.
While some have speculated that the chemical perfluorocarbon, an odorless and inert tracer gas used in the experiment, could be harmful to commuters during the 30-minute release, Brookhaven research engineer and principal investigator on the project, Paul Kalb, assures the amount of chemicals released are safe.
“We’re releasing a small amount perfluorocarbon, and what that does is enable us to see in very small quantities in the air and we get a sample and determine the concentration to see how far they’ve moved,” Kalb explained. “It’s really non-reactive in a chemical sense. The amount is an important consideration and this is nontoxic in high concentrations.”
The project will utilize nearly 200 sampling devices and be conducted during daylight hours in all five boroughs to ultimately find the pattern of airflow in an active subway system.
According to Kalb, similar studies to S-SAFE have been conducted for nearly 40 years.
“We have worked in Washington, D.C., and London with all the same materials,” he said. “This is not something new.”
The subway system sees nearly 5 million commuters each day, according to MTA statistics. Police Commissioner Ray Kelly explained the project is a crucial step in preparing for future terrorist attacks.
"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," Kelly said. "This field study with Brookhaven's outstanding expertise will help prepare and safeguard the city's population in the event of an actual attack."
MTA spokesperson Charles Seaton assured the project is safe, and is in the best interests of commuters and police responding to a possible chemical attack in the subway system.
“These gases are safe for our customers and employees, and the entire test will be performed with no impact on them and no interruption to service,” Seaton said.