I recently integrated a "Posting Room" Not a Chat Room, on my site (If I were to call it a chat room, posters would put in a lot of unrelated junk). It was a very interesting learning experience.
My goal was to have people post relevant information that was heard on the scanner along with professional discussion. Also a place to come to and find out what is going on with the local Police and Fire.
The result was a lot of trash talk.
My solution was to monitor all posts and have very strict guidelines that serve as the only warning prior to deleting the post or banning the poster. My recommendation is give it a lot of thought before you start a chat page. A "trash talking" chat page can make a site no one wants to come to.
Yakima Scanner Live Posting Room
YSL-Posting Room