heavily armed officers, and enhanced surveillance have been deployed to train stations and airports, while radiation detectors are scanning vehicles coming over bridges. >> this is the right thing to do. our experience that we've had in the last week or two and what we've seen all throughout the world, this is the right time to ou this. >> reporter: in the wake of this month's subway bombing, senator chuck schumer is calling for this scanner to be deployed in new york city. rt scans people as they enter the subway, looking for hidden explosives like suicide vests. tsst week, the los angeles transit system started testing it. es as that bar turns from green to red, we know we've identified an individual that may need a little closer scrutiny. >> reporter: alex wiggins is the l.a. m.t.a.'s head of security. >> if it detects something that is very dense, like what would be in a suicide vest or explosive vest, it will alarm and then it will give our officers an indication that here is something we need to take a akry close look at. >> reporter: the 6.4 million expected to fly in the next two weeks will also see security changes. new automated screening lanes