While the Transportation Security Administration (TSA) relies on data submitted by passenger carriers flying into the United States to determine the amount of air cargo they are screening, the agency doesn’t require all-cargo carriers for inbound flights into the country to submit screening data to demonstrate compliance with explosives screening requirements, the Government Accountability Office (GAO) says in a new report.

TSA doesn’t require all-cargo carriers to submit their screening data because the agency has been focusing its efforts on efforts around a mandate to ensure that 100 percent of all cargo carried on passenger flights into the United States is screened for explosives by Dec. 3, 2012, GAO says in the report, Aviation Security: Actions Needed to Address Challenges and Potential Vulnerabilities Related to Securing Inbound Air Cargo (GAO-12-632).

Without the screening data from the all-cargo carriers, “TSA does not know the extent to which all-cargo carriers are screening cargo or meeting the enhanced screening requirements introduced after the October 2011 incident in Yemen,” GAO says. The incident in Yemen refers to two bombs hidden inside printer cartridges that were sent from Yemen and destined for the United States but were discovered before final departure flights for the United States based on an intelligence tip.

GAO notes that the Department of Homeland Security has directed its components to adopt risk management practices and says that if TSA would assess the “costs and benefits requiring all-cargo carriers to submit screening data…the agency could determine whether these additional data could enhance the agency’s efforts to identify potential risks to inbound air cargo and develop cost effective strategies and measures to manage these risks.”

TSA is trying to get some visibility into all-cargo carrier screening operations through an ongoing pilot project that is being managed by its sister agency Customs and Border Protection (CBP). CBP began the Air Cargo Advance Screening (ACAS) pilot in December 2010 to find out if air carriers could submit air cargo manifest data before departure from a foreign airport and then determine if the agency could analyze the data, and take any necessary security measures, prior to the cargo being loaded on the aircraft.

GAO says that the DHS agreed with its recommendations that TSA assess costs and benefits for having all-cargo carriers report screening data. DHS also says that TSA is “taking steps to require carriers to provide confirmation that screening has been conducted in accordance with TSA’s enhanced screening requirements” as part of the ACAS pilot. In addition, DHS says the ACAS pilot will eventually be able to “report high-risk inbound air cargo shipments screened by all-cargo carriers.”