Invisible,odorless perfluorocarbon tracer gases released to test how vapors would travel through the US’s biggest transit system during a terrorist attackMen in orange vests released a harmless, invisible, and odorless gas on a subway platform at Grand Central terminal on Monday,part of a test of how air moves through tunnels and potentially how a biological contaminant would travel through the nation’s biggest transit system during a terrorist attack. There is no health risk. The gas contains tracing particles that stare like drops of perfume from an atomizer before quickly dissipating. Related: Plague, anthrax and cheese? Scientists map bacteria on unique York subway Continue reading...
Source: theguardian.com