PORTLAND, Ore. -- Is the home you're buying going to keep you and your family safe when the Big One hits?

Oregon lawmakers are considering a new bill that would require sellers to let you know.

House Bill 2140 would specifically let buyers know if a home was built before 1973. And if it was, has it been bolted to its foundation?

During a committee hearing, lawmakers heard from a leading earthquake expert why that should be important.

"We're all essentially built on a ticking time bomb," explained Oregon State University geologist Dr. Chris Goldfinger.

Goldfinger said new information out in just the last couple of months puts Portland and all of Northern Oregon at a higher risk of having a major earthquake than previously thought.

According to the quake expert, we now have about a 22 percent chance of having a magnitude 8 or higher quake in the next 50 years.

"Here the destruction level is going to be high and it's going to be a very long process in trying to rebuild," he added.

He said most at risk are older buildings or workplaces, but that most homes will fair just fine in a big quake as long as they are anchored to the foundation.

"Doing enough damage so that the house is unusable again is pretty likely if the house is not bolted," he said.

As for why the year 1973 is an important date for homes: it's the year builders were required to start anchoring homes to their foundations. Before that, many homes weren't attached to their foundations at all.