At chickendude's suggestion, you won't die immediately upon hitting a hazard or getting too close to a nuke.  The problem was how to make this work because of hazards such as water and lava.

I finally decided that the player will jump in the air upon touching a hazard, like you see in some cartoons.  Hitting any hazard will make you lose a shield, so the shield count have been raised to 5.

The exception will be the city in the clouds level (level 12).  Because the player dies from falling off the clouds and descending toward the earth in this level, it doesn't make sense to have him jump out of the way of "gravity"