What color is comfortable for Intranet?

Hi, Everyone...
 
I was involved in the project for improving intranet usability. 
 
So, my team has decided to propose develope style guide for intranet.
We decide almost of things for style guide...
 
But, now we need to decide the intranet's background color that is
comfortable for intranet users... Some peoples said Green or Blue tone
colors will be comfortable for eyse of users. 
 
I don't know What color will be really comfortable for eyes of users
who always use them everyday.... and why that color will be
comfortable...
 
I wanna know what color will be comfortable for intranet and why? I
hope the reason will be scientific, so everyone can be acceptable for
that reason.
 
Please give me some advice...
 
Thanx in advance...
 
Tony...from Korea... ^^;;