I watched a Neil DeGrasse Tyson video about teraforming Mars where he goes over the topic of UV radiation and how our ozone layer protects us. He makes a statement that the UV on earth is actually only a small percentage, about 3%, and furthermore only 5% of that being the more harmful UV-B which causes sunburn and skin cancer.
My question is, what would happen to a human if they were to receive the full dosage of UV-B radiation from the sun, let us assume 500 times higher than that on earth, with no protection? Would it be fatal? And if so how fast would it kill you?