employees also face background checks yearly updates. and a system built around everyone watching out for anyone who might seem suspicious. but the chief admits nothing is fool proof. >> at airports across the country, we have not really seen anything that could prevent what atlanta went through, which was guns being smuggled on to airports. >> i agree. i agree. in any airport throughout the united states and here also there is never a 100% guarantee that somebody couldn't who wanted to do something illegal or wrong, couldn't make that happen. >> reporter: what happened in atlanta, is causing a reaction at airports across the country. and you can see why. these are guns. guns smuggled on to as many as 20 flights by one delta airline baggage handler. that baggage handler took the