I have heard them called FANs (Field Advice Notices), SINs (Site Instruction Notices), and stop works, trying to mean the same thing (stop building something is wrong here) but without the legal clout.
It's a given that the other tools of good communication, persuasion, mediation have been exhausted. Some buildings are dangerous, unsafe, insanitary. No amount of political interference should expose the public to such risk!
This is the formal version from the Regulations.
If you would like some refresher training in this topic click the link below.
