The AAR.600 Program is being discontinued, since U.S. and international regulations have superseded the AAR.600 standard. As a result, AAR has immediately stopped registering tanks under the AAR.600 Program. The U.S. Department of Transportation's Pipeline and Hazardous Materials Safety Administration (PHMSA) plans to issue a rulemaking later in 2009 to remove from the regulations current requirements referencing AAR.600.