Spider Room Level 6
 

G'day on level 6 have gone up in lift & am in spider room have activated both switches have very limited ammo how do I kill spider.

Look around, there is plenty of ammo in this room... if not you can kill it with the axe also, wait for him to attack you, dodge his attack and hit him with the axe, also run few steps away faster... keep running and keep shooting is the way.

First to all thing , connect the energy in the hall to create heat ;) .

To make it even easier, go around the corners of the room and look at the pipes. One, instead of being straight, will stick out of a wall instead of the ceiling and then bend down to the floor. There is an opening that lets you go under the pipes. When you're there, the spidery guy can't attack you!

The corners offer HEAT and health increases via the steam pipes (once you've opened the two hatches after the elevator stops).

I've used all the corners successfully to prevent the spider from attacking me.