Harris Plant Siren Testing

The Shearon Harris Nuclear Power Plant is owned and operated by Duke Energy. All public emergency notifications related to the plant are issued by Wake County Emergency Management.

The Town of Apex shares the information below to help residents understand how emergency alerts, sirens, and preparedness communications work.

How Residents are Notified

Each year, Duke Energy mails emergency planning information to residents who live within a 10-mile radius of the plant. This information includes:

Outdoor siren testing

Duke Energy tests outdoor warning sirens throughout the year to ensure they are working properly.

2026 Scheduled Siren Test Dates

  • January 7 (5–30 seconds)
  • April 1 (5–30 seconds)
  • July 1 (5–30 seconds)
  • October 7 (up to 3 minutes)

What To Expect

  • Scheduled full-volume siren tests occur on Wednesday mornings to minimize inconvenience.
  • Most tests last only a few seconds; the October test lasts up to three minutes.
  • Additional individual siren tests may occur periodically throughout the year as part of routine maintenance.

If sirens are sounding and you do not see or hear an emergency message on local radio or television, contact Wake County Emergency Management for guidance.

 All information provided by Duke Energy. Check their website for more detailed information about the Harris Nuclear Plant. For complete safety and communications information, visit the Shearon Harris Nuclear Plant website.

NOTE: Beyond the schedule below, individual sirens are tested periodically throughout the year. 

Tone Alert Weather Radios

As part of the Emergency Preparedness Program, Duke Energy provides Tone Alert Weather Radios to residents living within a five-mile radius of the plant. Radios are tested annually.

If your radio is not working, contact the Harris Nuclear Plant Emergency Preparedness Specialist:

Residents Who Recently Moved

  • New construction home: If you live within the five-mile radius and are a Town of Apex Electric customer, you will receive a radio within four months of moving in.

  • Previously owned home: If the previous owner did not leave a radio behind and you meet the eligibility criteria, contact the Emergency Preparedness Specialist using the information above.


Additional Emergency Information: Sirens and Emergency Broadcasts

How Outdoor Sirens Are Used

To alert people who are outdoors, county officials may sound warning sirens located within the 10-mile Emergency Planning Zone (EPZ) around the Shearon Harris Nuclear Power Plant.

  • Sirens will sound repeatedly during an emergency.
  • The sound is loud and steady to get attention—not to provide instructions.
  • Hearing a siren does not mean you should evacuate.
  • Siren testing does not indicate an emergency 
  • No public action is required during routine tests 

If you hear a siren, tune to a local radio or television station immediately for information.

Emergency Alert System (EAS) Messages

When sirens sound, local radio and television stations will broadcast an Emergency Alert System (EAS) message from local officials.

These messages will:

  • Explain what is happening
  • Provide clear instructions on what actions, if any, residents should take
  • Be updated as the situation changes

Always follow instructions from local officials and stay tuned for additional updates.

Alerts for People Indoors

Outdoor sirens are designed to alert people outside and may not be heard inside homes or businesses.

If you are indoors:

  • Rely on local radio and television stations for emergency information
  • Pay attention to official emergency alerts
  • Follow all instructions provided by local authorities

Additional Emergency Notifications

During an emergency, fire, police, and rescue units may:

  • Patrol affected areas
  • Use vehicle sirens or loudspeakers to share information

Boaters in the area may also be alerted through marine sirens or loudspeaker announcements.