1. Take a scenario:
If there is a nuke coming towards an OP ETA 5. And i have my units attacking the OP ETA 6. The radiation stays for 10 ticks. As per the rule nukes affect everyone so if i forget to move my units from there till the radiation ends will the HP of my Units go down since they stayed on OP for 10 ticks.
2. What is the ratio of Army upkeep and Outpost upkeep which decreases the amount of workers from the worker growth??

1. Yes, sitting in radiation will lower your HP by 1 every tick that passes to a minimum of 1 HP.
2.

http://wiki.battledawn.com/index.php?title=Population

Here is a full list when it comes to upkeep.

Thanks Simmen. I myself forgot that I had a question here.