Why does OMS offer a choice of Retractable Band and well as non-retractable band BC's for technical diving?

Ocean Management Systems offers both styles of BC's, just as it offers a Hard/Soft Pack and Stainless Steel and Aluminum Back plate Harness Systems for various reasons.

The choice of Dive equipment is often based on personal preference and in some cases is selected based on the type of diving or location.

Perhaps the best analogy to this statement is that we do not all drive the same type of car, van or truck to get from point a to point b.

What about your new IQ pack, what is different about it?

The diver can now utilize a combination of available pockets or use none at all. The pockets can now be adjusted to the front or to the rear to allow easy access.

The stainless steel single cylinder adapter plate, as well as the aluminum or stainless steel back plate can be eliminated for use with singles making the new IQ pack, lighter and easier to travel with.

The IQ pack and the new non-retractable band BC's have been designed, tested and approved by leading divers in the Cave community as well as Ocean Divers.

What are the advantages of OMS retractable band BC's and what documentation can you provide to support your claims?

1. OMS Retractable band BC's are easy to orally inflate *¹
   
2. OMS Retractable band BC's assist in deflation *²
   
3. OMS Retractable Band BC's decrease drag when deflated *³
   
4. OMS Retractable Band BC's reduce the massive airshift associated with large non-banded BC's that occur when changing body plane. *⁴
   
5. OMS Retractable Band BC's have trim adjustability. That is by removing selected bands, differentially inflated parts of the BC can compensate for uneven weight.
   
6. The highly engineered OMS retractable and non-retractable band BC's have a proven safety record over a 10-year period and have been used under the most extreme conditions.

Argo Diving Service (an independent test lab)
Po Box 2289
Avalon Ca 90704
By Jon Hardy
Date of Test: November 9, 2000

We received two Single Bladder BC's with two IQ (stainless) Back plates (IQ M-L), two aluminum backplates, and two single tank adapters with cam bands on October 23, 2000. We assembled each of them and confirmed that they were correctly assembled with a phone call to OMS. The only difference between the two BC is that one was assembled with the retractable bands and the other assembled without.

Tests were conducted in Avalon Harbor on Santa Catalina Island, California. All tests, other than the drag tests, were done in 24 feet of water. The test diver and/or the BC's were attached to a mooring weight to allow for control.

Both BCs were inflated orally without undue difficulty.

The BC with bands took an average of 16.5 seconds to dump the air put in orally.

The BC without band took an average of 15.0 seconds to dump the air put in orally.

(Conclusion) This test indicated no significant difference between the two BCs, yet it did confirm that either BC could be inflated orally.

This test indicated no significant difference between the BCs, yet it did provide a basis for comparison with buoyant lift and rates of air dumping

Each BC was dumped multiple times using the remote exhaust on the top right of the BC, after being fully inflated.

BC with bands took an average of 20.5 seconds to dump all air.

BC without bands took an average of 25.5 seconds to dump all air.

(Conclusions) This test indicated that the BC with the bands is more effective at dumping air by use of this R/E (remote exhaust).

This test was devised to measure the approximate drag or resistance to movement through the water by a fully equipped diver with these two BC's (with and without retraction bands). The diver was secured by 15 feet of line behind a 25-foot commercial dive boat that was secured to a dock. The boat's engine was put in forward at an idle speed of 800 rpm, thus creating a current of 0.95 to 1.10 mph as measured by a calibrated underwater speedometer. Placed directly in front of the diver and attaching the diver to the line to the boat, was a spring scale. The diver took readings while in the current of the propeller wash at three to six feet underwater. The tests were repeated multiple times on two different days.

(Conclusions)

BC with bands caused an average of 6.3 to 11.3 pounds of drag when empty.
BC without bands caused an average of 7.5 to 11.5 pounds of drag when empty.
These tests indicate no significant difference in drag (when inflated).

(Conclusions) The BC wings (without the bands) move more (the airshift in the BC) and are less stable (than the BC with bands). i.e. The BC wings with the retractable bands are more stable)

These BCs are well suited to tech diving with or without the retractable bands. Their buoyant lift capacity is significant and within specifications. Both BC's (with and without retractable bands) can be inflated orally and there is not significant difference in this aspect of use.

There is no significant difference in either the power inflating or the oral deflating of these BC's. The BCs do dump faster than they inflate, which are a positive safety feature. The remote exhaust on the top right of the BC flows better when the BC has bands, although the BC without bands was still acceptable.

Copyright 2001 Duplication, alteration and/or transmission of this document is expressly forbidden by OMS and may result in criminal prosecution

All OMS BC's use a (2) bag system composed of an inner heavy duty flexible urethane bladder and a rugged 1000 Denier Cordura outer bag (shell) that is backed with a five (5) oz. Coating of Urethane for superior puncture resistance. On our non-retractable band BC's we add a virgin PVC strip to protect the top of the bladder. We strive to use the best materials possible regardless of cost.

Yes

Yes

Note: there is a recall on some BC OPV's. Check your serial #'s against the list on the recall page.