New York City is retiring many of its Cold War-era signs designating certain indoor spaces as "nuclear fallout shelters."

There are thousands of the signs around the five boroughs, but officials say they're misleading, and no longer denoate active shelters. That's because it's been decades since anyone has taken care of the facilities, which were designed to protect people from radioactive debris that falls from the sky following a nuclear explosion.

Jeff Schlegelmilch of Columbia University's National Center for Disaster Preparedness says now that nuclear tensions with North Korea are on the rise again, it's important to make sure there's no confusion.

"People are really noticing them again," says Schlegelmilch, "and there is a real danger of creating a perception that these shelters exist and that they're somewhere you could go, only to find out that in the shadow of a mushroom cloud you're walking up to a locked door."

While the threat of nuclear warfare hasn't necessarily gone away, city officials want the signage removed to avoid any confusion.

Hear WNYC host Sean Carson discuss the end of the fallout shelter era with reporter Jordan Gass-Poore.