Hunting New England Shipwrecks

Chip Kelly (at right) prepares for a deep dive on a New England wreck. Chip is an experienced tech diver. Over the past few years, the popularity of technical diving has grown dramatically. Tech diving is a step beyond normal scuba and allows specially-trained individuals to go deeper and/or stay down longer than standard scuba techniques allow. It involves the use of mixed gases and a variety of specialized gear and techniques. Technical diving is primarily practiced by cave divers and serious wreck divers.

U.S. scuba instruction agencies define technical diving as any one or combination of the following practices:
     • Diving deeper that 130 feet (on air or mixed gases) and/or
     • Mixed-gas diving (Nitrox, tri-mix, etc.) and/or
     • Decompression diving
Technical diving requires specialized training and certification. This training is is offered by selected regional dive shops and scuba instruction schools.

The jargon of tech divers is filled with terms like Nitrox, tri-mix, rebreathers, dive computers, decom tables, physiology, redundant systems, guidelines... and safety. And before anyone becomes a skilled tech diver, they have to learn about all these things in great detail.

Tech diving is not for everyone. Because of the depths and complexities inolved, it is a higher-risk activity than normal scuba diving. In order to become a competent and safe tech diver, you have to have the right stuff. Technical diving requires a combination of specialized training and equipment, a serious commitment to the activity, an understanding of the risks involved, and excellent physical and emotional health. Attempting to do technical diving without proper training and equipment may result in serious injury or death.

Because our editors are not qualified technical divers, we will not provide any original information on tech diving on this site. For anyone interested in learning more about the subject, however, we have included several Tech Diving links at the bottom of this page.

Tech Diving Commentary
By: Fred Calhoun

Of the three definitions of technical diving listed above, the one that's easiest to do is Nitrox diving. In order to dive with Nitrox (oxygen-enriched air), you must have specialized training and certification. When using Nitrox, bottom time is greatly extended when compared to using air. On a 60' dive, for example, one's no-decompression limit using Nitrox-I is double that for air (130 minutes vs 60 minutes). The depth limit for conventional Nitrox use is 130 feet, so Nitrox itself does not promote deep diving.

Diving deeper than 130 feet, and decompression diving, pose many more complications. If you're going to do that stuff, you need to be properly trained, have a good understanding of the risks involved, and have the health and self-discipline necessary to do it properly. You also need to have the common sense to know your limits.

And finally, one more thing... Technical diving is knowledge-intensive and experience-intensive, but it should not be equipment-intensive. Considering all the things you have to keep track of (depth, time, gauges, gas profiles, currents, etc.), especially at a depth where you may be narced, the simpler your equipment is, the better off you'll be. People who dive with too many gadgets have far too much stuff to keep track of. And when something goes wrong, they can't get out of the gear they've strapped to their bodies. I watch them every weekend. They make 40 foot dives and drag in enough junk to survive being shot to the moon. It's a problem!

Fred Calhoun is the Technical Diving Director for PDIC (Professional Diving Instructors Corporation) and a well-known New England diving instructor, author and charter boat captain. Fred is the author of PDIC's training manuals The Nitrox Manual, and Basic Technical Diving. Both of these books are available from the PDIC Website.

To go to other pages on this site, use the Site Navigator at left, or click here to go to our Home Page.