Community Alert Siren System

In the unlikely event of a general emergency at the San Onofre Nuclear Generating Station, those who live or work in the Emergency Planning Zone (EPZ) will hear a piercing siren that will sound steadily for three minutes at a time. This is the Community Alert Siren System.

Made up of 50 strategically placed sirens throughout the EPZ, the Community Alert Siren System for San Onofre provides reliable, prompt notification to the general public to turn on their radio or television for important information from local authorities in the event of an emergency.

Siren activation is a coordinated process among local jurisdictions. Jurisdictions are responsible for activating sirens in their community. As a backup measure, Orange County has the ability to activate all sirens except for those at Camp Pendleton.

Along with the sirens, roving public address systems and/or messages to home, cell or business phones via AlertOC are also a signal to turn on a radio or television and wait for instructions.

If the sirens have been activated, turn on the television or the radio to KWVE FM 107.9 (Santa Ana) or KOGO AM 600 (San Diego).

An Emergency Alert System (EAS) message will be delivered by radio and TV. It may advise you to stay inside with doors and windows closed, evacuate the area, or do nothing depending on the nature of the emergency. Recommendations on whether or not to ingest potassium iodide (KI) may also be delivered through these outlets. In pill form, KI can be used to help prevent the thyroid gland from absorbing radioactive iodine that could be released during an emergency at a nuclear power plant.

Southern California Edison (SCE) is responsible for installing, maintaining and testing the siren system. Ensuring that all the sirens will work properly in a real emergency is a top priority. The regular testing of sirens includes:

• Daily Silent Tests – Tests the connections between the sirens and control centers.
• Quarterly Growl Tests – Brief audible test of each siren to ensure siren will sound.
• Annual Siren Test – All sirens are turned on simultaneously for their full cycle by each jurisdiction. This test is normally conducted in the fall, during the morning hours, and sirens are sounded several times for approximately three minutes each time.

• Check radio and TV stations, as well as your city's web-site and this site, just as you would in a real emergency.
• Do not assume a siren might be a false alarm no matter what you hear from neighbors or friends. When in doubt, find out your city's emergency response team to provide professional guidance about how best to protect your family.