reactor
This map of radioactive deposits (measured by activity of cesium-137 in soil), in the immediate vicinity of the damaged reactor at Chernobyl, shows very high contaminations but very uneven. Activity exceeds 3700 kBq per square meter near the reactor and the city of Pripyat (40 times the dose rate of natural radioactivity)
These contaminations have led, on April 27, 1986, to the evacuation by the Soviet authorities of 116,000 people living within a circle of 30 km radius
UNSCEAR-2000
On April 27th, 1986, one day after the explosion, the Soviet authorities proceeded to the evacuation of 116,000 residents living within 30 km around the damaged plant. The area was evacuated in emergency within 30 hours and declared prohibited. The exclusion zone has since remained largely uninhabited, though defying the proscriptions, about 500 people, usually elderly, the "samosjoly" returned to live there, preferring not to leave the villages and the environments to which they were attached.
If one adds to these 116,000 inhabitants, people outside the zone who were also evacuated later, it is a total of some 350,000 people who had to suffer the trauma of uprooting imposed overnight and relocation.
The abandoned control room
In the centre of the exclusion area, the abandoned reactor and the control room. Mike Durst, a nuclear physicist at the IAEA: "Inside, you feel like in a tomb. Cold, wet and dark. Pipes burst, a lot of debris. You are going all over a series of mazes to reach the control room where operators controlled the reactor. The level of radiation is not too high, but if you go down below it is mortal "
NGM (The long shadow of Chernobyl)
Microsieverts, one millionth of a sievert and abbreviated as uSv (1,000,000uSv = 1Sv)
Dosimeters generally measure in microsieverts.
An older unit for dose is the rem (Roentgen Equivalent in Man), or the smaller millirem (abbreviated “mrem”) still often used in the United States. One sievert is equal to 100rem.
Roentgen’s are another measure, 1 Roentgen (R) equals 0.877 rem or 0.00877 Sieverts.
Radiation measurement Pripyat cemetery
A radiation measurement of 21.88 uSv/h at Pripyat cemetery
