Updated

Federal officials plan to make San Francisco International Airport the first in the nation to screen all passenger aircraft cargo for explosives.

The Department of Homeland Security, the Transportation Security Administration and airport officials signed an agreement Monday to launch a $30-million pilot program later this summer, then expand it to two other unannounced airports.

Lawrence Livermore Laboratory and several other national labs will help determine how best to apply existing luggage-screening procedures, such as bomb-sniffing dogs and X-ray machines, to cargo.

Last year, 235,000 metric tons of cargo was shipped out of SFO and only a small portion was screened, officials said. The goal is to screen all cargo without significantly delaying flights.

"We're going to try to increase the throughput by six times," said Homeland Security spokesman John Kubricky. "Cargo is the last thing to go on the plane. We don't want to hold up the plane so we need to speed it up."