At the Caravan club in Östhammar, the warning technicians Per-Arne Cedergren and Mats Blom set up a new "Hesa Fredrik".
It will give a strong warning signal if a nuclear accident in Forsmark occurs.
- The warning signal will cover the campsite and a small community further away, says warning technician Mats Blom.
It was the nuclear power accident in Fukusima in Japan in 2017 that made the government want to redo the safety zones around the nuclear power plants in Sweden and now about 50 new Hesa Fredriks are being set up in the area.
An inner and outer border
- The experience gained from the events in Japan is how we can protect the population as well as possible and at what distances we need to be prepared, says Tomas Roland, coordinator in nuclear energy preparedness at the County Administrative Board in Uppsala.
The new safety zones have an inner and an outer limit of 5 and 25 km respectively.
- We should be able to evacuate the inner zone in a few hours and the outer one sensibly.
But we can also evacuate up to 100 km, says Tomas Roland.
In September, it is hoped that all new Hesa Fredriks will be in place and tested.