Of course there are dangers to every level, but going through I have noted a few in particular that can be deadly with one shot and a slightly frustrating way to die if you are not prepared for them. Thought I would list the ones that came to mind out so you all can learn from my mistakes!

Cycorp Industries Level 4: Consumer Testing
My first death, never carry an explosive through the lasers at each point in the map. They will explode shortly after you walk through and provide an instant death. Disable a laser by going to the security checkpoint and using it to be able to carry the explosive. Also found on this map are puddles of water with electricity flowing through them. If you step on a puddle while it is being electrocuted, it will make you the past president of the being alive club.

Cycorp Industries Level 3: Product Development
The commandos found in this level (with the ARC cannons) seem to rival some enemies from the Delta-7 levels, and it is easy to get overwhelmed in these areas. Therefore, it is best to enter this level with friends, and more importantly to make sure that you do not rush in without a strategy.

Delta-7 Mining Facilities
There are spots in each (or at least I know the first two) map where rocks will fall at certain points in the maps. There are two strategies to beat this. The first is to run back to safety when the screen starts to shake and you sense that the rocks are about to fall. I would recommended either asking someone where each collapse in when you get in game (as they are hard to describe on the forum), or to test out where the rocks will fall and then to note their locations for later reference. Second, and much more dangerous, is to just run straight through them, which is what I had been doing for a long time. Usually, you can make it across without being hurt, but there is no guarantee that things will work in your favor. There is one in particular that has proven to be difficult to pass (and provided me with my second death), and that is the second rock collapse on the left side of Dead Man's Cave. Overall, the better strategy is to develop patience and to wait for them to fall before proceeding, but I know that can be difficult to do.

I am sure that I have missed a few, so if you have any additions of things that players should be conscious of to avoid a quick death, feel free to reply.