Scuba Regulators Buying Guide

Scuba Regulators Buying Guide

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Scuba Regulator

The Importance of a Regulator

Your regulator is one of the main pieces of scuba equipment that allows you to breathe while underwater.

There is an enormous array of regulators that offer a variety of features, shapes, and designs. Regardless of this brand or style you decide to use, a regulator consist of three parts: a first stage (frequently purchased separately), a brightly-colored 2nd stage, and an air hose.

1st Stage vs. 2nd Stage

The first stage attaches to the diver's tank via a yoke or DIN fitting. It regulates the air pressure as the air exits the tank before the air can enter the air hose. The second stage contains the mouthpiece and purge valve; the purpose of the second stage is to deliver the air into the diver's mouth and to remove any waste (air or other objects) as needed.

Diaphragm vs. Piston

Regulators can use either a piston assembly or a diaphragm assembly. The piston or diaphragm controls and reduces the air pressure from a high pressure to a moderate pressure in the first stage. Either design may be equally good and equally sensitive to the diver's inhalation needs except under conditions where high flow is required: there the piston regulator delivers much more air than the diaphragm regulator.

Piston regulators offer a very good air flow rate and generally have only one moving part. Even though piston regulators have fewer moving parts than diaphragm regulators, they tend to be more expensive because the machining process is so precise. Because piston 1st stages have fewer moving parts, they tend to be more reliable and less expensive to maintain. Diaphragm first stage has many moving parts but is much simpler to manufacturer, offering a lower initial purchase cost but lower performance (not generally noticeable within recreational sports diving limits).

Cold-water divers typically prefer diaphragm regulators because they are less likely to free flow in cold water than are piston regulators.

Purge Button/Exhaust Valve

The 2nd stage's exhaust valve is a one-way valve that allows the diver's exhaled air to leave the regulator. Basically, it is where the bubbles exit the mouthpiece.

The purge button allows the diver to force air from his/her tank through the regulator to clear any water that may have inadvertently entered the 2nd stage. This button should be fairly simple to manipulate, even when wearing thick dive gloves. It should also only require the pressure from one finger to successfully perform the purge.

Din vs. Yoke

There are two types of coupling fittings that are used to attach a regulator's 1st stage to the tank: DIN and Yoke.

Yoke couplings are more commonly found world wide and are almost always used by the ever-popular aluminum 80 tanks.

DIN fittings are safer than yoke fittings and are the only fitting that can couple with high-pressure tanks. The advantage of DIN fittings is that they screw into the tank valve and trap the high-pressure o-ring so it cannot protrude, like can occasionally happen when using a yoke fitting.

A DIN-style regulator can be equipped with a yoke adaptor, which screws onto the threaded part of the DIN-style 1st stage. This style of adaptor is somewhat cumbersome if you frequently use yoke- style tanks .

A Yoke-style regulators can be equipped with a separate DIN adaptor, which replaces the yoke portion of the 1st stage on a semi-permanent basis. DIN adaptors should be installed by a qualified scuba repair technician at a full-service scuba shop. This option is preferred if you frequently use DIN valve tanks.


Scuba Regulator

Simply put, balanced regulators offer a steady breathing experience, regardless of depth or air pressure in your tank. It is very rare for an unbalanced regulator to be preferred over a balanced regulator.

An unbalanced regulator will leave you feeling like you're struggling somewhat to breathe as your tank's air diminishes and as you descend and the pressure exerted on your body and gear increases.

Balanced regulators leave you feeling like your breathing effort is steady throughout your dive. The one downfall of balanced regulators is they are a more complicated piece of gear than are unbalanced regulators; therefore they tend to have a higher purchase price than unbalanced regulators. Balanced regulators compensate for depth and decreasing tank air pressure by equalizing the pressure on both sides of the air valve.


Your 2nd stage's mouthpiece is a more crucial piece of equipment than most people believe. A mouth- piece should be comfortable in your mouth; if it feels too big or too small, elect to use a different size mouthpiece. Mouthpieces are typically made from hypoallergenic silicone, which is a pliable, yet sturdy material.

More and more mouthpieces are touted as being ergonomically shaped. This is a great advantage be- cause it means your jaw will maintain a natural position, which should decrease your changes of experiencing post-dive jaw pain.

Because mouthpieces wear out with repeated use, it is highly recommended that each diver keep a spare mouthpiece in his/her dive bag. Some divers incorrectly bite down hard on their mouthpieces, instead of softly cradling the mouthpiece between the upper and lower teeth. This results in the bit areas separating from the main portion of the mouthpiece. If this happens, the mouthpiece must be replaced before return- ing to the water.

Regulator Accessories:

  • Regulator Mouthpiece

    Spare Mouthpiece

    Regulator mouthpieces wear out over time. Keeping a new mouth piece in your dive bag will ensure that you have a comfortable and fully-functioning mouthpiece whenever it is needed.

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  • Scuba Mouthpiece Sanitizer

    Mouthpiece Sanitizer

    Before putting your 2nd stage's mouthpiece into your mouth, make sure it is free of germs and other infection-causing foreign bodies.

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  • Scuba Regulator DIN/Yoke Converter

    DIN/Yoke Converter

    Most scuba regulator manufacturers offer conversion kits that allows the fitting type to change. A scuba technician can use the coupling conversion kit to switch your fitting type.

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