Pretty good concept, but I would have loved to see some scoring to motivate the player. Also when the radiation comes, you don't have too much time to escape. Other people would be cool to walk around (and die).
The graphics are cool, I love the game over screen, also the walk cycle, especiall the side view looks really nice. The game needs to be improved, but it's not bad. With more gameplay element and variety, it could be better. Like on some days, something special happens. Breaking the monotony, giving the player new challange.