Mask

A mask is an item of diving equipment that allows scuba divers, free-divers, and snorkelers to see clearly underwater. When the human eye is in direct contact with water as opposed to air, its normal environment, light entering the eye is refracted by a different angle and the eye is unable to focus the light. By providing an air space in front of the eyes, light enters normally and the eye is able to focus correctly.

How to fit a mask

  1. Put the mask on your face (without using the strap) and make sure your Hair is not tugged underneath the silicon Skirt
  2. Gently inhale into the mask until it sucks onto your face (you should not have to use any force to push the mask onto your face).
  3. The mask should stay on your face with the initial suction you created. If you have to continuously inhale then there is not a good seal and the mask does not fit well.
  4. Most masks have an inner and outer seal. Look into a mirror to make sure that both of these seals are sitting firmly against your face and the inner skirt not over your eyes.
  5. Make sure that there is nothing uncomfortable about the mask. If it bothers you now, it will be bothering when you dive.
  6. Now that you have the mask on, look around and check your vision.
  7. Silicone color black has the advantage that no light is coming inside the mask and your iris will open compare to a transparent silicone skirt which can have the effect of a mirror where you will see yourself on the lenses. but for claustrophobic people better!

Interested to buy a good Mask? Have a look at our Online Shop!


 Explanation and description of the different types of masks:

Construction

Diving masks may have a single, durable, tempered glass plate in front of the eyes and a “skirt” of silicone to create a watertight seal with the diver’s face. There are rubber skirt masks on the market but the water seal is better with a silicon skirt and it doesn’t smell. Some masks may have two lenses, which in some cases allows the user to fit prescription lenses. In the case of freediving masks, which need to be low volume to minimize the change of pressure that occurs with depth, the lenses may be made of polycarbonate plastic. All masks have an elastic strap to keep them in position.

Masks that are used at depth must be constructed so that the diver can exhale through the nose into the mask to prevent the “squeeze” caused by increasing pressure during descent in water.The nose section of the mask also needs to be flexible to allow the diver to perform an equalization maneuver such as the valsalva maneuver or the frenzel maneuver when equalizing pressure in the middle ear.

Some masks have a one-way purge valve under the nose to let water out. The diver simply holds the mask upright and exhales through the nose. While common in snorkeling, this feature is less favored by SCUBA divers because of the possibility of the valve failing at depth and leaving the user no means of clearing his mask. A simple and effective method for clearing a diving mask while underwater is to look down, place a finger on the top of the frame at either side, and slowly look up while exhaling through the nose.

Sometimes masks are sold in conjunction with snorkels and/or swimfins. Low quality snorkeling masks may have a low-quality plastic or glass faceplate, and are not recommended for anything but rare, casual use. Masks that have the snorkel built in are considered hazardous as well.

Divers often test whether a mask is a good fit by placing it on their face, without using the straps, and gently inhaling through their nose. If the mask stays on without any help this indicates that no air is being drawn in and that the fit is good.

Use

To prevent a mask from fogging up due to condensation on the glass plate many divers spit into the mask, wipe the spit around the inside of the plate and wash it out with a little water. There are commercial products that can be used as an alternative to the saliva method.

Refraction of light entering the mask makes objects in salt water appear about 33% bigger and 25% closer when underwater. As the diver descends, the water acts as a color filter eliminating the red end of the visible spectrum of the sunlight entering the water leaving only the blue end of the spectrum. Depending on the depth and clarity of the water, eventually all sunlight is blocked and the diver has to rely on artificial light sources to see underwater.

A variety of prescription lenses can be fitted inside the glass plate of the mask to correct some visual problems underwater. Divers may be able to use contact lenses inside the mask but they must keep their eyes closed if they remove the mask underwater to avoid losing the lenses. Double-dome masks restore natural sized underwater vision and field of view, while also correcting for a certain range of myopic vision. Mask removal and refitting is a basic skill that all divers are taught so that the diver can overcome floods or the mask being dislodged without panic.

When entering the water while wearing the mask, the diver normally needs to place a hand over the mask to disrupt fast water flow during entry. This prevents the mask from becoming dislodged or the glass damaged. Alternatively, a diver can enter the water with the mask off and then put it on or use an entry method such as the “forward roll”, where the diver rolls forward with head entering the water first, which does not result in fast water flow over the mask.

Mask should always be rinsed inside and out with clean, fresh water after each day’s use, and dried off after washing. A mask should not be stored in direct sunlight for long periods of time as ultraviolet light degrades the silicone. A well-maintained mask will last for many years.

Take your time!!!

Be sure to try on several masks. The more you try on the more you will start to figure out what you like and don’t like. Be sure to take your time with each mask. Make sure that it feels very comfortable and fits your face well. Since the mask will be your most important piece of gear. Good Mask come in stiff boxes which is great for the transport so they don’t dis-form!

Interested to buy a good Mask? Have a look at our Online Shop!

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