Radiation and Cs-137
Aktualizace: 11. říj 2018
What are the levels of radiation in the Zone nowadays after more than 30 years since the accident? And is radiation the biggest danger you should avoid during your exploration? You will find all basic information regarding this topic outlined in this post.
After the Chernobyl accident the levels of radiation in the power plant and in the nearby areas (including the city of Pripyat) ranged from 0.1 to 300 Sieverts per hour (almost billion – 1,000,000,000 times more than the usual natural background radiation measured in microSieverts - μSv). Mostly radioactive isotopes of iodine 131, caesium 137 and strontium 90 were thrown into the air. Spending even 10 minutes around the burning reactor would result in Acute Radiation Sickness (ARS) and cause hazard to life.
Nowadays the evacuated areas remain wasteland, however, it is very hard to find radioactivity that exceeds the natural background radiation. Also, that is one of the reasons that the 30-kilometre exclusion zone has now been turned into a nature reserve. Within the 10-kilometre zone you can still find radioactive hotspots, i.e. spots on the ground with condensed radiation that still exceed the natural level by a hundred and even a thousand times.
During one day spent in the Chernobyl exclusion zone the body receives a dose of radiation comparable to the natural background radiation found all around us. To put this in perspective, this dose is typically 300 times less than a whole body X-ray scan and is comparable to several hours spent on an aeroplane, where we are more exposed to cosmic radiation coming from the outer space.
The body receives a dose of gamma radiation comparable to 0,0005 dose by X-ray scan or to 3-5 hours spent in an airplane. In numbers, you will receive 3-5 microsieverts of gamma radiation – an absolutely non harmful dose of radiation. For comparison, most of the nuclear power plants around the world have a safety limit for their employees set at 50-100 microsieverts per day. During a one-day tour you will get even less: 4-6 microsieverts of gamma radiation. Most probably you will get more radiation during flight to Kiev.
Visitors to the Chernobyl exclusion zone should avoid radioactive dust, which might occur at some places and get stuck in small (not dangerous) amounts on their clothes or shoes. Due to this, I suggests that all explorers should wash all their clothes and shoes thoroughly as soon as they return home.