Deep diving is sort of a relative term, as a deep dive for one person may not be a deep dive for another. Books have been written about deep diving and there has been much controversy over the years with respect to how to deep dive, what gasses to use, decompression techniques, etc. If you’ve browsed around on some of the training websites, you probably noticed a specialty certification called Deep Diver. What does that mean exactly? For training agencies like NAUI and PADI, this certification teaches you to dive from 60 to 130 feet (18 to 40 m) following no decompression requirements. You also probably noticed that if you were to take an Advanced level certification, you would also be exposed to at least one deep dive.