Here are some of the example questions. There were plenty of questions as well for multiple dives and proper surface interval from the charts, or the max dive time and depth allowed for the second dive. All answers needed to be derived from the dive charts. None were just simple questions, all required the use of a partial answer from chart one and or two, with the final answer coming from chart three or variations of this kind of chart use.

Other questions were something like this:

Absolute pressure at a depth of 131 fsw is:

The ocean depth at which the PPO2 in air is equal to 1.6 ATA is how many feet deep assuming 21% O2

breathing .5% carbon monioxide at 131 feet is equal to what percentage at the surface

What Percentage of O2 is required to remain concious at Sea level.

These were the kinds of questions on this 100 question exam. You could get 20 wrong and pass, ( 80%) There are a lot of things involved with this type of class that greatly exceed the typical interests people do for recreation and entertainment. The math could leave an average highschool student perplexed. Should be reasonably challenging for a college grad, and for me at 59 years old having been out of both for a very long time, quite a refresher on study habits and practice.

Even though I have a EE degree, this was more than I expected in the courseware. I also do not use this kind of math even in my job frequently. I think this is important information to know and understand for some types of careeres in Scuba. However, for the majority of recreational divers much of this course may not be helpful to you. I enjoy the complete understanding of the science regarding this process, connecting all the dots to understand the entire event even from a mathmatical perspective. I can say that I have not needed to calculate much of the data that was required to know in this class in a decade. It's much easier to learn how to use a dive computer and trust that device than to try to remember and calculate all the data from the charts required to derive a dive plan within your NDL.