Used when you're away from your desk, but haven't gone far - If someone needs you, they should come and find you.
Usually used
if there is a chance that you might need to render
assistance to someone in a hurry, and your reason for being away is flexible and not so
important that you can't leave it or even cancel it altogether.
"I'm awailable - just getting a snack from the kitchen."
"They should still be
in the building - they said they were awailable. Probably just chatting with a friend."
"I'm
getting some lunch. Seeing as you have that
important call, consider me awailable if you need assistance, and I'll come help you out. I'll be down the hall."