LIANE HANSEN, host:
The discovery of explosives on those cargo planes has led to calls for tougher screening of air freight. U.S. carriers have already been ramping up security of cargo that travels on passenger planes since Congress passed new requirements in 2007. But, as NPR's Larry Abramson reports, shippers say that screening everything shipped by air would slow things down and cost lots of money.
LARRY ABRAMSON: The 9/11 Commission recommended screening of all cargo that goes on passenger planes. So back in 2007, Democratic Congressman Ed Markey helped pass a law that requires total inspections starting in August of this year. Now, Markey says this most recent incident is a sign Congress should go further.
Representative ED MARKEY (Democrat, Massachusetts): It does not have to be identical to cargo carried on domestic planes, but I don't think we can be completely reliant upon intelligence provided to us by Saudi Arabia or other countries.
ABRAMSON: Markey says he will introduce legislation to that effect. But cargo flights carry at least four times as much freight as passenger planes, so that would mean a massive expansion of the inspection system.
Brandon Fried represents shippers as head of the Airforwarders Association, an industry group. He says that just inspecting the seven billion pounds a year that goes on commercial flights is already very expensive.
Mr. BRANDON FRIED (Airforwarders Association): We've invested, you know, hundreds of millions of dollars in the last few years to accomplish the task that was mandated by the 9/11 legislation.
ABRAMSON: Fried says that's what it costs to pay for devices that detect explosives and radiation. Those are covered in the end, he says, by consumers.
While the TSA inspects passengers and their luggage, shippers and airlines inspect the cargo that rides in the hold of those passenger planes. Much of this work occurs through the Certified Cargo Screening Program. Shippers who sign up become trusted and they can speed their packages along by following a series of protocols, according to Hans Weber, who's with a consulting firm called Tecop.
Mr. HANS WEBER (Tecop): Once you're a trusted shipper, you also have certain responsibilities for notifying authorities if something is amiss, et cetera. And you have the responsibility for knowing something about the people to who you're shipping for.
ABRAMSON: This allows industry to police itself without the need for big TSA inspection stations. But it also creates disadvantages for smaller shippers, according to Michael Whatley of the Air Cargo Security Alliance, another trade group.
Mr. MICHAEL WHATLEY (Air Cargo Security Alliance): They do not have the wherewithal to get the screening equipment put in place at each of their facilities.
ABRAMSON: So, Whatley says, a shipper in, say, southern Illinois might have to truck his packages up to Chicago and have them checked out at the airline's facility at O'Hare Airport. That adds time and expense. And, Whatley says, the program also has limited capacity, so it leads to what he calls stranded cargo.
Mr. WHATLEY: They basically said if it has not been screened, it will not be put on the plane. Well, they're not screening 15,000 tons a day. If it gets screened, then it goes on the plane. And if it doesn't get screened, it does not go on a passenger plane, as of August 1st.
ABRAMSON: So, some packages have to wait for the next flight.
But Congressman Ed Markey says industry always says security is too expensive.
Mr. MARKEY: The chemical industry has not wanted to put extra security around its chemical plants. The nuclear power industry has not wanted to put extra security around their nuclear power plants.
ABRAMSON: That's why Congress must mandate these steps, Markey says.
Shipping analysts say the 9/11 attacks focused attention on passenger screening. Now, the focus will shift to cargo until another plot exposes a new weakness.
Larry Abramson, NPR News, Washington.