This thread
http://www.ukclimbing.com/forums/t.php?n=619337 about a recent accident has generated a lot of discussion about the importance of clear communication. Whilst there seems to be widespread agreement that the term "safe" has only limited application in sport climbing, if at all, it seems less clear what calls should be used.
Trad climbing of course has a well-established pattern of calls which apply both to single- and multi-pitch, So far as I am aware there is no agreed system of calls for sport. I admit I am not a regular climber of bolted routes, but from my observations both outdoors and indoors people seem to use a variety of calls, or none. IF there is a standard system of calls they don't appear to be very widely known or used. "How to" articles in magazines explain how to arrange lower-offs but I don't recall seeing anything about calls.
Moreover, the routine for trad climbing is much the same whether it is single- or multi-pitch. Sport on the other hand has several different possible scenarios at the top of a pitch. I can think of at least four, each of which require different actions by both climber and belayer:
1) clip (to fixed krab or climber's own quickdraws) and lower off
2) make safe and rethread the rope through the fixed anchor
3) set up an abseil
4) on multi-pitch, bring up the second to continue climbing
Behaviour at the top of the route also seems to vary, with some climbers being willing to clip and immediately jump off while others (including me) want to know they are being firmly held on a tight rope before commencing lowering.
Apart from the multi-pitch scenario, the established trad calls don't seem to fit the bill. So, should there be an accepted standard for sport climbing calls, and if so what should they be?