Now this might be a idiotic question / suggestion, but shouldn't there be some increase in ambient temperature when you are caught in the reactor-implosion*?
I mean, you get this huge fireball and all that, yet you can merrily keep firing lasers, PPC's, and SRM's despite the fact that mech's core just blew up 20 meters from you.
(*or explosion? I'm not really sure what the correct term here is.)