21 REGULATORS

THE DEEP BREATH TESTS

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REGULATORS: IN CONCLUSION

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THE important thing to remember is that all the regulators worked - it is just that some seemed to work better than others. The sometimes disparate opinions of our testers reveal the importance of personal preferences.
The issue of mouthpieces seemed to achieve a significance far beyond what might be expected of an item that costs comparatively little. However, a mouthpiece that allows you to breathe through closed teeth might be comfortable to retain in the mouth, but is more likely to chill your teeth and might affect the ability of the regulator to deliver the maximum quantity of air, should it be needed.
On the other hand, a mouthpiece that achieves optimum air-flow could hold the jaw so wide open that it would become uncomfortable after a short period. The ANSTI machine tests the regulators without mouthpieces in place.
Our practical diving comparisons certainly did not extend any of the regulators to the limit, but they did reveal that a highly tuned regulator that is delivering air with the least effort can also be guilty of providing a positive pressure that at times will result in excess air being lost through the exhaust port.
This can happen when facing a fast current. No one wants their precious air-supply wasted in this way.
Manufacturers tend to publish nice neat performance graphs achieved with their product under pressure but not under water. We found that immersion in water in the ANSTI machine made a lot of difference, and was obviously more relevant to the real diving situation.
Under these conditions one regulator, the Ocean Reef 6600, came up with a result that looked positively dangerous.
AP Valves MD Martin Parker, operating the ANSTI machine for us, said he was very disappointed in the performance of all these regulators! Unlike most regulators he had tried previously, these were not fresh out of the box. This raises the question of the relevance of the EN250 test. Are present requirements sufficient?
What we did find was that several regulators came out well with both our testers and the ANSTI machine. Although many of these, such as the Scubapro Mk20/G250 and Mares MR22 Ruby, were among the most expensive, the cheaper Scubapro Mk14/M50 and Mares MR12 Voltrex were equally favoured. Clearly lower prices do not necessarily mean inferior performance.
Other good ones were spread over the whole price-range and included the Apeks TX40, the Oceanic Delta II D, the Ocean Reef Enterprise TR94, and even the very inexpensive Spiro Ranger XP (to be replaced by the Calypso) and the Cressi-Sub F3.

NOTE: Following our tests Apeks, unaware of our findings, told us it had discovered "a dimensional error in the first-stage hp balance plug" of its new TX100 regulator. This, it said, could adversely affect the breathing performance of some of the 40 samples manufactured to date, including the test unit. The error has apparently been corrected..

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The Deep Breath Tests | ANSTI Testing

Apeks TX40 and TX100 Beuchat Evolution and VS8 Club Cressi-Sub XS1 and F3 Mares MR12 Voltrex and MR22 Ruby Ocean Reef 6600 and Enterprise

Oceanic Delta IID and Gamma D Poseidon Cyklon 5000 and Jetstream Scubapro Mk14/M50 and Mk20/G250 Sherwood Blizzard and Magnum Spiro Ranger XP and Supra D XR2 Cryo, US Divers SEA4 Micra ADJ

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Appeared in DIVER - March 1998.

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