They're too high to live in (for human standards) and far too high to cultivate food in.
However, for a week visit you're likely to have no more exposure than a chest x-ray. Also the measures they're proposing would certainly help. It sounds like the 'tourist' portion where you're outside exploring you're likely wearing something akin to disposable scrubs to mitigate the radiation inside the buildings (where you're likely to spend 1/2 your time anyway).
I went there last year on a tourist trip - walking around the exclusion zone and through the abandoned buildings was an amazing experience and I'd recommend it to anyone.
In all honesty, one can rate most radiation sources as 'pack of cigarettes per time'.
A lot of Cherynobyl is pack a week. Closer areas is pack a day. Some of the hot areas are pack an hour. And you stay the hell out of the pack a minute areas.
However, for a week visit you're likely to have no more exposure than a chest x-ray. Also the measures they're proposing would certainly help. It sounds like the 'tourist' portion where you're outside exploring you're likely wearing something akin to disposable scrubs to mitigate the radiation inside the buildings (where you're likely to spend 1/2 your time anyway).