This statement from the FCC announces that from here on out all VHF DSC radios must be equipped with a test function. The test function should help alleviate some of the problems the Coast Guard is having with VHF DSC false alarms.
From the press release: Effective today (25 March 2011), the U.S. Federal Communications Commission is prohibiting the manufacture, importation, sale and installation of fixed mounted (non-portable) digital selective calling (DSC) equipped marine radios that do not meet the requirements of International Telecommunications Union (ITU-R) Recommendation M.493-11 or higher, and in the case of Class D VHF DSC equipment only, International Electrotechnical Commission (IEC) International Standard 62238. Therefore, effective today, radios built to RTCM Standard SC-101 can no longer be manufactured, imported, sold or installed; however, previously-installed radios meeting the older standard may continue to be used.
In practical terms, radios meeting these newer standards must have a test call capability compatible with the nationwide Rescue 21 service, and must have a autoswitching inhibit capability allowing users to keep their radios from automatically changing frequency channels when DSC calls are received.