SeleaingAKsntutorBY JERRYDRAYTON, JR.U.S. DIVERSI'ar too many divers complerea recognized courseof instructionin basic skin and scubadiving without really knowing how to select a regulator intelligently. Most experienceddivers and instructorsrely on their knowledgeof various brandsand are rarher careful when it comes to selecting a regulator, But the beginning scuba-diver"knows only what he is told eirher by the instructor or what he readsin diving manuals and professional magazines.Some of the pertinenr details concerningreguiarors are contained in the following paragraphs.This simpleguide shouldprove usefulto the prospective regulator buyer. There are two major categories' of regularors.One is rhe two hose requlator which was frequently seen on ihe old "Sea Hunr" relevisionseries: the other is the more modern and widelv rusedsingle hose regulator. There arl also subcategories such as single stage two hose,two stage two hose and two stagesingle hose.

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Co nshe lfXll, left Aquarius, right

Aqua-Master, left Royal Aqua-Master, right

Calypso lV, left CalypsoJ, right

DACOR ':e-*

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*tH)Olympic 200 Olympic 400

Olympic 800

Olympic 100

Two hose model R-4

Two hose model C-3

68 sKfNorvrn/NovransER 1972

In the two hose regulator, the entire demand mechanism is housed in one unit. There are two corrugared hoses-one leading from the air chamber to the diver's mourhpiece and the other going from the lefr side of the diver's mouthpiece to the warer chamber. The hose on the right supplies the diver with air; the hose on rhe left carries expired air to the water chamber where it is discharged. The air and water chambers are separated by a flexible, watertight, airright diaphragm. The regulator mechanism functions on rhe principle of pressure differential. Air inside the air chamber is eqr.ralto surrounding water pressure, lVhen the diver inhales he creates a pressure differential in the air chamber, the diaphragm is depressed and air flows to the diver. \fhen the diver exhales, pressure on each side of the diaphragm equalizes and air flow is discontinued. Two hose regulators are either one stage or two srage regulators. Stage refers to a reduction from tank pressure. In the one stage two hose regulator there is one reduction from tank pressure to breathing pressure, There are two reductions from tank to breathing pressure in the two srage regulator. The single hose regr.rlator differs from the two hose regularor in the location of the demand valve. All single hose regr-rlatorsare rwo stage. The demand mechanism is housed in the second stage. The stages are separated by a flexible intermediate pressure hose. The hose acts as an intermediate chamber transporting air between the two stages. The first stage is connected to the tank valve and reduces the cylinder pressureto an intermediare preisure (usually 8 5 to 1 40 p. s . i. ) . I t is r r ans ported through the hose and breathed at ambient pressure from the second stage. The choice between a single hose or dorrble hose regulator. in the cese of a novice diver, will generally depend upon his initial contacr with the equipment. He will usually prefer the type and brand of regtrlator he used in his basic class becar.rse this is the resulator with which he is most fam iliar . The s ingle hose regrrlator is most often preferred, however, because of its economy of operation and lower initial cost. The simplicity of the single hose regulator makes it extremely easy to maintain. The diver can usually make most of the necessary repairs himself. $7hen it does require professional service, it can usually be repaired more cheaply than the two hose regulator. A good single hose regulator can also be purchased for less than the cheapest two hose regulator curently on the market. The single hose regulator now dominates the market and the number of available two hose models has dropped from eight to five in the past year.

AMF VOIT, INC.

Swim as t e rM R - 1 2

SwimasterTitan ll-R12J

Swim as t e rT i t a n l l - R 1 2

S w i m a s t e rL i t t l e G e m l l l - R 1 0

Swim as t e rP o l a r i sl l - R 1 4

Avalonlll-Vl20

Gonquerorll-VL22

Viking l-V124

WHITE STAG

Pictured above is the Oceanaut and at r i g h t ( b o t t o m ) i s t h e Dreadnaught. At right (top) is t he Aquan e t i cl l .

S K IN D IV E R /N OV E MBE1972 59 R

HEALTHWAYS

Scub airSon ic

Sc uba i r" J "

Scu ba ir Sc ub a i r " B " Scub a Star

POSEIDONPoseidonCyklon 300, right

SPORTSWAYS

WaterlungW-300J

Hy dr onaut lll

Sport Diverlll

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WaterlungW-200

WaterlungATM-5004 1972 70 SKINDIVER/NOVEMBER

However, the two hose regulator does have certain advantages. The two hose regulator has a definite advantage for the undetwater photograoher. Bubbles ate exhausted behind the diver where they cannot interfere with vision and picture taking. Since the hoses contain air, this makes the mottthpiece lighter and more comfortable over prolonged use. Two hose regulators generally inhale harder than single hose regulators, but it is also easier to cxhale. The question most often asked by prospective regulator buyers is, "How much does a good regttlator cost?" The answer to this question depends largely upon the needs of the inclividtral diver. Regulator prices range anywhere from $40 to over $200 depending on the manufacturer and features of the regulator. For the occasional diver who o n l y d i v e s t h r e c o r f o t r r ti m e s x ye a r , the moderately expensive regulator will suffice quite adequately. These regulators range in price from $15 to $80. The more serious diver will probably want to consiclcr the more expensive professionalmodels. A regulator classif ied as prof essional must deliver a minimum of 21 cubic feet of air per minute at 2500 p.s.i. ProfessionalreguIetors rangc in price from $90 to over $200. For those who plan to become involved in deep ancl strenuous dives, there is no srrbstitute for the professional regtrlator. is The quality of a regLrlator measured by its performance. Hence, making a regulator selection in the store from a static display is cxtremely difficult. The internal mechanism and clesisn determ i n e a i r f l o w : r n , l b r c rr tl r i n g ch e r a cteristics in regulators. Pcrformance cannot be determined in the swimming pool. True regulator performance can only be measure.l by sensitive instruments designed prirnarily for the purpose of calibrating the suction effort reqtrired to obtain the flow of air needed by a working diver. One diving e q u i p m e n r m a n u f a c t r r r e r su m s i t u p adequately-"See Us At 200 Feet, \7e'll Show You The Differencel " This manufactr.rrer has a valid point, because at 200 feet the difference between good performance and poor performance in a regr.rlator becomes very apparent. Medical tests conducted by the U.S. Navy have proved that it is more fatigLring to exhale against a resistance than to inhale against a resistance. A good regulator can facilitate inhalation, but nothing can be done to facilitate exhalation. This means that the exhaust valve is of key importance to the overall performance of the regulator. \7hen selecting a regulator, the buyer should be careful to choose a regr.rlator with

W at er l u n gA T M - 7 5 0

large exhaust ports. A regulator that draws slightly hard on inhalation but exhales easily is much less fatiguing to the diver than one that draws more easily but exhales harder. Aside from breathing performance, the regulator buyer should be aware of the special features on the regulator he intends to purchase. A high pressure port for the attachment of a submersible tank pressrrregatrge is a necessary feature. The importance of this instrument as both a tool and safety device is well-known. Diving authorities agree that the submersible tank pressure gauge is no longer to be considered a luxury, but a necessity for safe diving. Another feature which is considered desirable but not necessary is an additional low pressure port. This feature permits the attachmenr of an additional second stage to the firsr stage to make what is popularly referred to as an octopus rig. The octopus rig is coming into its own as a valuable diving tool. It is the ideal regulator for cave and wreck diving, and its superiority in buddy breathing is r.rnchallenged. The purge button is also a featute worthy of consideration. The diver should be able to depress the pruge button even while wearing gloves. Most regulators have covers over the diaphragm to prevent the purge from being depressed accidentally. Others place the purge button flush with the second stage housing to prevent the occrurence of accidental purging. The regulator market represents a source of constant confusion for many novice divers. There are nine ma jor manufacturersof diving equipment who together market more than 40 differenr models of regulators. It is, therefore, rupto each prospectivebuyer to acquaint himself with regulators and the important featnres of various models. Great care should be taken in selecting a regulator. The regulator is the single most important piece of equipment a scuba diver owns. A Door or hasty regrrlator selecrion can ciipple a diver's future enjoyment of the sport. The doubtful regulator shopper should not be hesitant to seek professional advice. The local pro dive store or the diving instructor are usually very cooperative, and they may be able to help alleviate some of the confusion about buying a regulator. In the final analysis, the choice of which regulator to buy depends entirely upon individual performance needs and the amount of money a diver plans to spend. But, as a diver, you will get more out of your selection if you seek professional advice and adhere to guide lines in the preceding paragraphs. >#

S E A MLE S S / MRO D NE

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SCUBAPRO

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S c u b a o r oM a r k V l l

S c u b a p r oM a r k l l l

S c u b a p r oM a r k V l SKIN DIVER/NOVEMBER 7I 1972