In the fall of 2005 , responding to inter-organizational communication problems during the rescue operations after Hurricane Katrina , the United States Federal Emergency Management Agency ( FEMA ) discouraged the use of ten-codes and other codes due to their wide variation in meaning . The Department of Homeland Security 's SAFECOM program , established in response to communication problems experienced during the September 11 attacks also advises local agencies on how and why to transition to plain language , and their use is expressly forbidden in the nationally standardized Incident Command System , as is the use of other codes
September 11 attacks
September 11 attacks
Ten-code