Have questions about emergency sirens? We have answers.

Updated Jan. 2019

We always expect our nuclear stations to operate safely, but in the unlikely event of a nuclear station emergency, we’re prepared – and we want you to be, too. We have a variety of ways to keep neighbors informed, including sharing emergency preparedness information in booklets mailed to homes and on our nuclear social media channels.

However, the notification method that most people associate with nuclear emergency preparedness is the network of sirens located within a 10-mile radius of each plant. The sirens would be used to alert people outdoors in the unlikely event of an emergency at one of our nuclear energy facilities.

With populations around our nuclear plants constantly changing, we are often asked about the sirens as they are tested throughout the year. To answer some of those frequently asked questions, we sat down with Lee Jackson, a nuclear emergency preparedness specialist at Robinson Nuclear Plant.

What’s the purpose of sirens around nuclear plants?

Jackson: Sirens are used to alert people within the 10-mile emergency plan zone of our nuclear plants of an emergency.

How likely is an emergency at a nuclear plant that would require the sirens to be sounded?

Jackson: Due to rigorous maintenance and well-trained staffs at nuclear power plants, the probability is very low that we will have an emergency. However, local jurisdictions (counties) ultimately determine when and if the sirens are sounded.

Why are nuclear emergency sirens regularly tested? What’s the schedule?

Jackson: Sirens are tested regularly to ensure they are operating correctly and are always in a ready state. The sirens are tested weekly using what we call a “silent test” that cannot be heard by the public. Once a quarter, we conduct a full volume test of the system.

Why are sirens sometimes tested on days other than what’s listed in emergency planning calendars?

Jackson: Sirens can be sounded on non-scheduled days as part of our preventive maintenance program or after necessary maintenance.

Do the sirens really have to be that loud?

Jackson: Yes. Sirens are meant to alert people who are outdoors. The sound level of the sirens is governed by Federal Emergency Management Agency (FEMA) and Nuclear Regulatory Commission (NRC) regulations. They are designed to exceed summer daytime background sound levels so they can be heard.

What should people do when they hear a siren?

Jackson: In the unlikely event of an emergency, people should tune into local TV or radio stations for instructions on what actions they should take.

What if plant neighbors hear a siren but aren’t sure if it’s a test or not? Where can they find out?

Jackson: First, they should look in their emergency planning calendar, which is mailed at the end of the year. Information in the calendar is available on our website as well. Neighbors can also follow our nuclear fleet on Twitter or follow our Duke Energy Nuclear Education Facebook page.