Sirens and the Alert and Notification System

No matter how unlikely the chances of an emergency, nuclear power plants are required to have emergency plans to handle any incident. Constellation Nuclear has emergency response plans for Calvert Cliffs and Nine Mile Point. The plans are approved by local, state, and federal government agencies and are tested regularly in emergency drills.

The Alert and Notification System

• In an emergency, Constellation would inform state and county officials at once. County officials would activate the siren alerting system within a 10-mile radius of the power plant.
• The sirens are installed to promptly alert the public to any potential danger.
• The sirens are not a signal to evacuate.
• The sirens would sound a steady three- to five-minute signal, which varies in loudness as the siren rotates.
• If you were to hear the sirens, you should turn on your radio to a local Emergency Alert System (EAS) station and listen for instructions.
• In almost all cases, an accident at Calvert Cliffs would take several hours to develop into a major emergency. During those hours you would be notified and would have time to take precautions.
• Remember, the sirens may be used to alert the public to other emergencies (such as tornadoes). In some areas a shorter siren signal is used to notify the local volunteer fire department and/or rescue squad members of a fire or rescue emergency.

What to do if you hear a siren

• Stay calm. Don’t panic.
• Check it out. The siren could be only a test, or it could be an accidental or faulty sounding.
• If you are not sure, assume it is real. A real warning could mean tornado, fire, chemical hazard, nuclear accident, or other emergency.
• Tune your radio to a local Emergency Alert System (EAS) station and listen for instructions.

Siren Testing Schedules

Regular siren tests in each county follow the schedule below. Radio announcements are not made for siren tests.

• Calvert County: An approximate 15-second siren sounding during the second full week in February, May, August, and November. A full three-minutes test on the first Monday in November. Silent test are conducted every week.
• St. Mary’s County: An approximate 15-second siren sounding during the second full week in February, May, August, and November. A full three-minutes test on the first Monday in November. Silent test are conducted every week.
• Dorchester County: An approximate three-minute siren sounding at noon on the first Monday of each month. Silent testing is performed every week.

Silent testing should not cause the sirens to sound. A complete, full three-minute test of all sirens is performed on the first Monday in November at noon. Radio and newspaper announcements are made to inform residents of the date and time of the annual test.