So I have a scene where the characters are having a conversation while something is on the TV in the background.
The characters in the scene (James and Nick) are talking at the same time as the characters on the TV. (Interviewer, Dr Hastings and Dr Steinberg)
The idea is that the chatter of the TV is heard under the main dialogue and also seen in the scene.
I know about simultaneous dialogue but how would you best describe the scene? Is this acceptable?

James switches the TV to a different channel.
On the TV In the B.G. an angry INTERVIEWER grills DR HASTINGS and DR STEINBERG.

Any other views or comments about this kind of scene is also welcome.
Yes the scene is necessary.
Thanks guys and gals.

It's perfectly fine to use b.g. but I tend to stay away from these kinds of abbreviations in the action lines, I just write "in the background" - that is, if it's needed.

The way I read your two action lines I'm not entirely sure you even need to mention that the TV is in the background. You have already mentioned that the TV is on and, for me at least, that would be enough.

You could use an INSERT shot of the TV screen but if you want the dialogue to flow well you could do something this:

      JAMES
Blah blah blah

      NICK
Indeed.

      DR HASTINGS (ON TV)
That's perculiar.

or

      DR STEINBERG
    (on TV)
I concur.

Thanks Sniper. I Like the suggestion and will go with that.
Thats the trick isn't it? identifying what you can lose without confusing the reader or losing any "colour" (yes, I am English!)

It also depends on if the dialogue on TV is important. If it's just background chatter, then you don't have to do anything but to indicate that the television is there and that it is on. Maybe describe the program if it is important.

If the dialogue in the television is equally important as the action in the foreground, then the most radical option is to split your script to two panels and write the parallel action on either of the panels. But that isn't a very good way to tell a story since nobody can follow what's going on properly. However, it is a valid format as I've seen it in several produced screenplays. Usually for only very brief moments at a time.

Thanks Henrik. Yeah Dual Dialogue is pretty messy on the page. Some of the TV is important and gives more information to the reader/viewer if they catch it so i'll have to keep it short and sweet so the dual dialogue format doesnt distract.