I tried adding a script to add damage over time. it definitely seems possible and would be better. Next time I work on this. damage over time would be a better outcome.

Well done! I enjoy your composition, but wouldn't it be better if the player recieved "damage over time" instead of just dying straight ahead.

I can suggest you to take a closer look at these two: https://forums.bohemia.net/forums/topic/217071-radiation-script/
https://forums.bohemia.net/forums/topic/204364-i-want-make-radiation-trigger-effect-but-that-doesnt-hurt-with-item-on-you/

I have tried them both and they work.