A new security law says that by July 2012, all cargo containers destined for the U.S. must be scanned and sealed at a foreign port before being loaded.

Under the 9-11 Act, which President Bush signed Aug. 3, containers will have to be scanned by non-intrusive imaging and radiation detection equipment. The Secretary of Homeland Security has authority to extend the deadline for two years if scanning devices are not available, don't work well or cause significant delays in container movement.

In other provisions, the law:

• Requires the Department of Transportation to come up with an analysis of hazardous materials routes. It gives DOT a year to document existing and proposed radioactive and non-radioactive hazmat routes and devise a method for states to gauge the safety and security of those routes.

• Gives DOT and the Transportation Security Administration six months to come up with program for tracking truck shipments of security-sensitive materials, including communications, position tracking and a way for drivers to send out a distress signal.

• Prohibits certain convicted felons from receiving a Transportation Worker Identity Credential.

• Tightens cargo screening requirements for passenger aircraft. It says that data checks of cargo must be paired with a physical or non-intrusive screening method. TSA has three years to comply.