In reply to Sgt. Vest:
In what way do you mean recognised? In the us there are many people that refer to themselves as guides who work for umbrella organisation that will have no qualifications. As such the way guide work below usage level in the US seem fairly adhoc. In that often the issue for working is getting permission to work in park, as state or national park will offer confession to guide to only certain centre or businesses. It is often the businesses that employ you and they will more often than not do some form of in house training or assessment.
As for whether it is on the same level I have a vague recollection that the syllabus is half way between our SPA and the MIA in terms of content. But check that.