This is a series of quizzes covering technical diving material, you will find content from International Association of Nitrox Divers, inc., Scuba Schools International, Scuba Diving International, etc.
One thing is certain, you must have the Encyclopedia of International Association of Nitrox Divers to complete some of the written exams, including the tables. This is so, because it is the most comprehensive book available for divers.
The minimum diver level knowledge’s is Advanced Enriched Air Nitrox or Recreational Trimix to understand and answer correctly these quizzes.