What would you do if a nuclear attack took place in NYC tomorrow? Would you commandeer a vehicle and head straight for the highways? Or would you be paralyzed with fear, waiting for Will Smith to rescue you? According to a new risk analysis study out of Stanford University, you'd be best off going underground, and hiding in a subterranean dwelling for a while.

The analysis modeled the impacts of a detonation in downtown Washington D.C. and calculated that clogged exit roads would pose more significant risks by exposing evacuees to radiation than if people were to remain in place at the center of large buildings or in basements. They recommend that people take shelter in basements or behind thick office walls for 12 to 24 hours. According to a post-9/11 study, an estimated 250,000 people would be killed in a nuclear attack in NYC. Researchers say sheltering would actually save more lives in NYC than in D.C. for three reasons:

New York city’s population density is much greater and so the population affected by the fallout would increase by nearly an order-of-magnitude; New York city has many more tall buildings, which would allow for greater protection for those who shelter; and New York city has few roadways that exit the city, which would greatly exacerbate both pedestrian and vehicle evacuation.

The study doesn't mention how preventative and preparedness measures might affect the outcome of such a scenario, nor what to do in emergency scenarios not involving nuclear attacks. But with many people assured that some kind of attack will take place eventually, it can't hurt to have some plan in mind, just in case. Or you can always fall back on old faithful, and hide under a desk.