I think the explosion card is quite harsh. I use a triple A deck and or double B deck, so many chances for a Boom! I came up with a random damage list to use when an explosion card is drawn. 1/6 will be a Boom, but with the rest there are still many other bad things happening.
Use two d6, preferably different color. One for the 10s, one for the one's.
Explosion Card Random Events.doc
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