ESS Testing Site Emergency Alarm

Emergency preparedness zone
Emergency preparedness zone around ESS. Image: City of Lund

On Monday, 2 June at 15:00, coinciding with the regular national emergency warning system test (known as Hesa Fredrik), the ESS area alarm will sound for the first time across parts of Brunnshög in northeastern Lund. The signal consists of a 5-second siren followed by 7 seconds of silence, repeated over a period of two minutes. The goal is for the signal to be clearly audible across the designated emergency preparedness zone, which extends approximately 700 meters around the ESS facility. The test will help determine how far the signal can be heard.

The Site Emergency Alarm will be tested multiple times before ESS enters full operation in 2027/2028. During normal operation, the ESS will generate a limited amount of radioactivity (ionizing radiation) as a by-product. However, all areas where radiation or radioactive materials are present are shielded with absorbing materials and equipped with safety systems to prevent any spread.

In the event of an accident, there is a possibility of radioactive release, which could expose individuals within the preparedness zone to a radiation dose. If the Site Emergency Alarm sounds in such a situation, everyone within the 700-meter zone – including the roughly 400 meters that extend beyond ESS’s own premises – should immediately go indoors, stay inside, close doors, windows, and ventilation, and listen to Swedish Radio, follow SVT, or consult krisinformation.se for updates.

Therese Geber-Bergstrand, radiation protection expert in emergency preparedness at ESS, explains: "The radiation dose the public might be exposed to in such a scenario would be roughly equivalent to an advanced X-ray examination, such as a CT scan. That said, the alarm remains a critical precaution. Like other facilities handling potentially hazardous materials, ESS must have an area warning system in place."

ESS works closely with Lund Municipality and the regional rescue services (Räddningstjänsten Syd) on all safety and emergency-related matters connected to the facility. Ahead of future tests and the next phase of commissioning, local residents and businesses will receive further information about what the alarm means and how to respond in the event of an emergency.

Note: “Hesa Fredrik” is the commonly used name for Sweden’s outdoor public warning system, officially known as “Important Public Announcement” (VMA). It is used to quickly alert the public in the event of serious incidents, accidents, or crises.