No offense to the original poster, but this is one of those recurring questions that drive me mad. I blame the earlier editions of the game for this kind of thinking (where a fireball expands to fill every cubic foot of area within its volume).
Yes.
Many people have been caught in the radius of grenades and mortars and walked away unharmed. I've seen video footage of a bombsquad technician accidentally setting off a bomb 2 feet from his face, and he got only partially singed hair. (Ironically, they said that had he been wearing his helmet at the time, the heat would have gotten trapped under it and killed him.)
Why does this question never come up for lightning bolt?
Quasqueton