Study: Estonia's personalized emergency alerts speed up delivery

Estonia's emergency alert system, which tailors text messages to the recipient's preferred language, has cut warning delivery times from hours to around 40 minutes, according to a new study. The research, by Stella Polikarpus of the Estonian Academy of Security Sciences, was published in the International Journal of Disaster Risk Reduction.

Previously, emergency alerts were sent as a single message in three languages: Estonian, Russian and English. The trilingual format proved too long, difficult to read and slowed down delivery, as messages were often split over several SMS segments, increasing network load.

'Testing carried out in 2022 and 2023 showed that trilingual alerts were too long and difficult to grasp in emergencies, reducing their effectiveness,' said Kadi Luht-Kallas, project manager for the EE-ALARM language preference project. 'We needed a solution that takes language preferences into account.'

Since 2023, EE-ALARM has used mobile operators' data to determine a person's preferred language. When no data exists, users receive a dual-language message in Estonian and English. In the May 14, 2025 nationwide test, 14 percent of recipients fell into this category; by the 2026 test, the share had dropped to 7-8 percent, according to Luht-Kallas.

The 2025 test sent SMS alerts twice to nearly 1.5 million SIM cards and was the first to include sirens. Some 24,787 people responded to a feedback questionnaire on kriis.ee. Of those, 97.8 percent said they had received the text message, and 68.3 percent noticed the SMS before sirens or mobile apps. Meanwhile, 95.6 percent said they could immediately read key information in their preferred language.

The study noted that under the old system, sending the same number of messages would have taken several hours and required close to 12 million SMS segments. With EE-ALARM, the alerts reached people in about 40 minutes, using 2.4 million segments. The authors described the location-based, language-aware SMS alert system as unique in the world.

However, the study also found room for improvement. The accuracy of language preferences depends on how up-to-date mobile operators' data are. Sending messages to phones with foreign SIM cards proved problematic, as the system often could not confirm whether roaming users had received them.

Researchers also looked at cell broadcast technology, which could deliver alerts faster and define danger areas more precisely. But they concluded that the solution needs further development, and any new technology must still ensure alerts reach people in their preferred language. They recommend expanding emergency alert channels and improving the quality of language preference data.

Real-life incidents involving stray drones during Ukraine's strikes on Russian infrastructure in spring gave the system additional testing opportunities. Estonia's alert system can cover all types of emergencies, including natural disasters.