We often hear that the zone is safe. When you visit with a guide who forbids you to enter any buildings, you don't have to worry about, of course. The ban on entering the buildings, preceded by an earlier ban on going onto the roofs,
is slowly becoming the norm for tourist groups. The regulation has been in effect for a long time, but it's being implemented more often. This comes as no surprise, if you look at the increasingly decrepit buildings.
Those who want to come to the exclusion zone of Chernobyl have to file documents for a permit two weeks before their visit. Then they are instructed at the checkpoint: visitors are not allowed to smoke, eat in the open air, take any
plants or items away from the zone, drink water from the wells, rivers or any other ground sources. Bodies should be covered with clothes leaving as few exposed areas as possible (the seamless apparels are preferable).