A minimum amount of 10 years is needed to get the basic pension (which is proportional to years worked), but years on Universal Credit (benefits) count towards this. Also, anyone who is of pension age is entitled to a Pension Credit top-up to a weekly income of £227.10.
You mean, everyone watched the TV story which has little basis in fact. Chernobyl was the worst case scenario - there's no way to build a reactor that would produce worse radiation effects when destroyed than to use a pile of graphite.