Thanks to research and equipment advances, today’s divers are taught a new set of skills. How up-to-date are you?
Recreational diving is still a relatively young sport. Created in the 1950s, it gained acceptance in the ’60s and ’70s, boomed in the ’80s and took great technological leaps in the ’90s. So there’s a good chance that not everything you learned in your open-water class still applies. New research and equipment have made diving safer and more enjoyable than ever—if you know the new rules.
1. Reverse Dive Profiles Are OK
New Rule
It is permissible to dive deeper on your second dive than on your first, and to dive deeper on the later part of a dive than on the early part.
Old Rule
Until this year, all divers have been taught to go to their greatest planned depth early in the dive and then gradually work upward in a regular “stair-step” pattern. Similarly, they’ve been told to make the deepest dive of the day the first one. The rationale was that the shallower depths later provided decompression for the preceding greater depths.
Reason for the Change
Dive computers. Because computers can track your depth and time constantly and are pretty good at math, it’s possible to know your nitrogen exposure accurately regardless of your profile. Tables, by contrast, can account for only your greatest depth, and this crude approximation of nitrogen exposure still mandates a conservative approach.
Exceptions to the Rule
Obviously, divers using only tables must still follow the old rules. And even when using a computer it’s still smart to dive deeper first. Ascending profiles give you more bottom time and a greater margin of safety against DCS.
2. Lower Minimum Age
New Rule
The Recreational Scuba Training Council, which sets many industry standards, dropped its minimum age requirement for junior certification near the end of 1999. As a result, PADI, SDI, SSI and NASDS (which has merged with SSI) have dropped their minimum age requirements for junior certification to 10. SSI has a pool-only “Scuba Ranger” program for 8- to 12-year-olds. NAUI and YMCA are retaining the age-12 minimum, at least for now.
Old Rule
Minimum age for junior certification was 12. (Junior certification requires supervision by a fully certified adult.)
Reason for the Change
To promote the sport. Lots of baby-boomer divers have kids, and the growing popularity of resort diving meant a market for family dive vacations. “The future of diving will be determined by kids,” says Bret Gilliam, president of SDI, the first agency to lower the age. “It’s a great step forward to recognize the family unit as key to our sport’s growth.”
Exceptions to the Rule
It’s still up to the instructor to decide whether a child is mature enough to dive. Being 10 does not create a right to be certified.
The new junior certifications typically have various restrictions. In PADI, kids are limited to 20 feet in confined water first, then 40 feet in open water. Juniors must be accompanied by an agency-affiliated instructor, a certified parent or another certified adult. Check specific agencies for their rules.
3. Universal Referrals
New Rule
Getting certified? Beginning in 1998, you could take classroom and pool sessions in your hometown from an instructor with Agency “A,” then fly to warm water for open-water sessions under an instructor with Agency “B”—as long as the agencies had agreements to recognize each other’s standards and instructors. This means you can choose from many more warm-water resorts for your open-water sessions.
Old Rule
Classroom, pool work and open-water dives all had to be with the same training agency. If you wanted to do the open-water dives in the tropics, you had to pick a resort with an instructor affiliated with the same agency.
Reason for the Change
Customer convenience. Smaller agencies with few instructors in place at resorts found it necessary to band together to offer greater options—especially when certification standards are virtually identical.
Exceptions to the Rule
PADI. According to PADI, it issues 70 percent of all certifications. The agency still requires that all phases of your training be with PADI instructors.
4. Slower Ascent Rate
New Rule
Ascend no faster than 30 feet per minute—one foot every two seconds.
Old Rule
The usual rate was 60 feet per minute until the U.S. Navy adopted the 30-foot-per-minute rate in 1996 and training agencies followed suit.
Reason for the Change
Research. Navy studies found that a 30-foot-per-minute rate resulted in fewer cases of DCS than the older 60-foot-per-minute rate. A slow ascent is really a rolling decompression stop, allowing your body to flush out and exhale dissolved nitrogen before it forms bubbles.
Exceptions to the Rule
The 30-foot-per-minute rate may not always be practical for the whole ascent, especially when you are deep and low on air or approaching hypothermia. In that case a faster rate, up to 60 feet per minute, is acceptable, ….
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