You can calculate some effects, like intensity of radiation and pressure waves, but others, like lethality, and trickier. Within a certain range of radii, your chances of survival depend strongly on where you are and what you're doing. Are you in a building sturdy enough to not collapse on you? Is there anything heavy that might fall on you? Are you near a window? Will the building catch fire?
A lot of this stuff made its way into building codes, after some nuclear tests to figure out what worked.
A lot of this stuff made its way into building codes, after some nuclear tests to figure out what worked.