Emergency override system

Local Access Alert

Type	Emergency warning system
Country	United States, others
TV stations	Some broadcast television stations and cable systems
Broadcast area	Mostly areas that have not upgraded to the Emergency Alert System
Launch date	Unknown
Dissolved	Unknown
Replaced	Emergency Bulletins
Replaced by	Emergency Alert System

The Local Access Alert (also known as Local Access System or Emergency Override System) is a warning system designed to warn radio, television stations, cable television broadcast feeds or satellite signals of impending dangers, such as tornadoes, flash floods and other civil emergencies. The system has been largely replaced by the Emergency Alert System in the United States, although it still exists in some areas which have not yet been upgraded, and is still used from time to time in areas that have upgraded to the EAS.

History

With a gradual transition from analog to digital cable, the Local Access Alert has been phased out and replaced by the Emergency Alert System, which employs Specific Area Message Encoding technology to activate for potential disasters and deactivate to resume cable broadcasts, especially late at night when many public servants aren't available to break in.

The first known Emergency Override Systems or Local Access Alerts were delivered during the boom of cable television in the 1960s, although it was not directly (and mainly) called the two main names of systems, as they sometimes pronounced it in various names. In the late 1960s and early 1970s, Local Access Alerts began to spread all over the United States, although few cities and towns had cable television yet. When cable systems continued to grow, the Local Access Alert was usually added.

Slide used during a test in 1982

Local Access Alerts gained the most popularity on local cable systems from the latter half of the 1970s until the end of the 1990s, when the Emergency Alert System took over the role of the Emergency Broadcast System on cable television on January 1, 1997. The Emergency Alert System began to build up on most cable television systems through the installation of then-new generators and encoders between 1997 and 1999. Some of the notable EAS generators at the time include Video Data Systems, Texscan, Gorman-Redlich, Idea/Onics, and Cable Envoy; and encoders include SAGE, TFT, and Trilithic models. During the cable growth of the Emergency Alert System, only some cable systems retained the Local Access Alert equipment up into the first part of the 2010s.

In the late 2000s and early 2010s, most remaining cable systems set up for Local Access Alerts used either both Trilithic EASyPLUS or Video Data Systems as their modern screens instead of the previously used older systems such as CommAlert (although older systems of the Local Access Alert were still used in a handful of areas at the time). By the end of the 2010s, the popularity of Local Access Alerts became nearly extinct on most cable systems in the United States, as all cable systems already had the Emergency Alert System, which at that time, local cable systems had become either Comcast, Time Warner Cable, or Suddenlink among others.

As of the early 2020s, most Local Access Alerts are delivered as practice or demonstration warnings as part of the Emergency Alert System, but the remainder of the nearly-extinct Local Access Alerts can still be seen on a minority of very small cable systems that either haven't had equipment upgraded or became part of a major company in unincorporated or very minor areas.

Purpose

Police or emergency management let viewers know of an impending disaster and instruct them to shelter or evacuate.

Local Access Alerts are activated for all kinds of emergencies, chiefly for weather warnings, watches, and advisories – such as tornadoes, flash flooding, or severe thunderstorms – in local and surrounding areas comprising the viewing area of the cable system. Other reasons include civil emergencies and major weather events (earthquakes, blizzards, winter storms, hurricanes, and tsunamis), Amber alerts, traffic closures, 911 outages, forest fires, dam failures, train derailments, and road conditions.

Activation procedure

The Local Access Alert is initiated by local law enforcement or emergency management staff, much like the antiquated Emergency Broadcast System, by dialing a number and entering a PIN through a telephone to take control of the cable of an area in the path of danger. Cable subscribers in that area have every television channel interrupted by audio and often a given screen. The distinct attention signal played can be Morse code, a siren, DTMF tones, steady single (or dual) tones, or multiple hi-lo beeps. The screen shown can be black, white, colored depending on warning, a slide or static. More modern alerts use a black screen with the words "Local Access Alert" in all capital letters with a message stating that "a local authority has initiated a direct community access"; the text was generated using the Trilithic EASyPLUS character generator (the same one used for the Emergency Alert System).

System tests

Tests of the Local Access Alert occur once weekly at randomly selected times, as well as scheduled monthly tests and yearly tornado drills. These alerts resemble the format used for activation of the Emergency Broadcast System and the Emergency Alert System.

Limitations

The problem with the Local Access Alert system is that the operators would have to dial out to end transmission. Simply hanging up the phone connected to the system after an emergency broadcast would not work, and sometimes viewers would hear other phone noises – such as off-hook tones or dial tones – before cable programming resumed.