Don't forget that these terms don't necessarily give you what status to set the emergency services to, thats determined by what the actual problem is.
5milesbaby
Thats exactly my point what you put on is determined by the nature of the problem as reported by the pilot , not what is determined by management,who want a full emergency irrespective of the apparent seriousness of the problem.
If all incidents are to be treated the same why bother having two categories of emergency.i.e Mayday ( big problem)
Pan
( spot of bother old chap ,would appreciate you give me a degree of priority, but I should be OK)