In reply to homing-penguin:
When you say "keeps an eye" do you mean in a horribly beauraucratic big brother kind of way? if so then no, not really. There are things like the HSE, WAHR etc which must be adhered to and the ABC does provide guidelines which must be followed by members but there is no obligation for walls to join.
In essence people who go climbing must understand that it is a fundamentally dangerous thing to do and should assess each situation individually while walls should do everything that is "reasonably" practical to ensure the safety of users. The place this becomes difficult is in the application of the word "reasonable".