There are 444 radiation portal monitors (RPMs) deployed at seaports throughout the U.S. for screening containerized cargo but some of these systems either aren’t being used or are infrequently used at best, the Department of Homeland Security (DHS) Office of Inspector General (IG) says in a new report.

Customs and Border Protection (CBP), the agency that operates the RPMs, and the Domestic Nuclear Detection Office (DNDO), which tests, acquires and deploys the systems, are “not always” monitoring the use of the RPMs and relocating them within seaports as necessary, says the report, United States Customs and Border Protection’s Radiation Portal Monitors at Seaports (OIG-13-26). “Finally, DNDO and CBP do not accurately track and monitor their inventory of radiation portal monitors.”

With both the shelf-life of and the funding for RPMs limited, the agencies need to “better coordinate to fully utilize, promptly relocate, and properly maintain inventory to best use resources and to continue screening all containerized cargo entering U.S. seaports, the report says.

During its site visits, the IG found 14 of 185 RPMs that were either being used infrequently or not at all, including four systems at one shipping terminal that hadn’t been used since Feb. 2011. In addition, three systems were not being used due to a seaport reconfiguration begun in Jan. 2011 and another two just hadn’t been used sine Jan. 2011, the report says.

The IG also says it couldn’t determine why DNDO and CBP deployed the numbers of RPMs that they did at various seaports.

In addition to the 444 deployed RPMs, 46 others have been removed since their initial deployment, some of which are to be relocated, the IG says, citing CBP.

“Without documentation to support how CBP and DNDO made initial deployment decisions, we were unable to determine whether RPMs were unused or being removed because they were not properly deployed,” the IG says. “It is not clear whether DNDO and CBP considered all critical factors needed for deployment.”

The average useful life expectancy of RPMs is 10 years, which means some of the equipment will become obsolete by 2014, the report says. The life expectancy can be extended with maintenance and improvements but so far DNDO has not taken steps to do so and hasn’t decided on a potential replacement technology, it says.

Following a recommendation by the IG, CBP and DNDO are working to create a single program office to coordinate and manage the RPM program.