...........is opinion. How they differ is factual. I do not have access to the standards of all agencies, so a comparison of them all is impossible. People will tell you all agencies meet the RSTC standards therefore they all have the same standards. This is simply not true. They all meet or EXCEED RSTC standards. An objective look at them will show they are very different regardless of how "alike" people tell you they are. You will find a small % of instructors in all agencies who exceed agency standards and teach a very good class. The vast majority of instructors follow agency standards to the letter. If that instructor's agency has high standards you'll get a good class. If that instructor's agency has standards on the low end, you'll get much less out of your class. None of the agencies are perfect, they could all improve.
There are two major viewpoints on teaching diving. Only you can decide which viewpoint is right for you.
Viewpoint 1.
Diving is fun and easy. It is possible to make the course easy as well if we eliminate skills that might possibly frighten anyone on their first day of class. If too many skills are included it results in task loading which will interfere with a student learning necessary tasks and make them an unsafe diver.
Viewpoint 2.
Diving is fun and easy. It is possible to make the course easy as well if we begin with simple skills and allow plenty of practice time on each skill. Once a simple skill is mastered, other elements are added to the skill allowing plenty of time to practice each element. When those added elements are mastered, still more elements are added in the same manner. By approaching skill development in this manner we are able to teach quite complex skills in a manner that makes it easy for students. Skills that might seem frightening to a student on the first day of class are a logical and easy progression by the time those skills are presented in class. This gives a student confidence and the ability to solve problems without panic.
Some agencies use viewpoint 1, others use viewpoint 2. There are some which fall somewhere in between. There are more than 2 agencies. Most divers are PADI certified. PADI is the largest agency by far. PADI follows viewpoint 1. NAUI & YMCA follow viewpoint 2.
Decide what's best for you, then interview potential instructors. Find out how the instructor teaches. What does that particular instructor include? Agency is merely one factor among many in deciding which course to take, it is not necessarily the most important factor.
For a point by point comparison of the standards of three of them go to
http://diverlink.com/newdiver/agencycomparison.htm
For a fairly complete list go to:
http://diverlink.com/training/agencies.htm
HTH,
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