Scuba Diving Masks and
Swim Goggles

By Liz DeFranco, ABOC, NCLC, with updates by Gary Heiting, OD;
additional contributions and review by Donald S. Teig, OD

Scuba diving masks and swim goggles can sharpen your vision and keep you and your eyes safer while you swim, snorkel or explore underwater.

If you normally wear eyeglasses or contact lenses, you'll have a better time underwater if you have similar vision correction instead of going without. So consider having a lens prescription inserted into eyewear adapted specifically for these activities.

Why Scuba Masks and Swim Goggles Are Needed

Light behaves differently in water than in air, distorting what you see. Particularly when you are swimming or diving, objects appear larger and closer than they actually are. This can hamper your eye-hand coordination.

Swim goggles and diving masks work by providing a pocket of air in front of you that enables light rays to travel to and through your eyes in a more precisely focused way.

Without that chamber of air in swim goggles and diving masks, your eyes would contact the water directly. Because light rays cannot effectively travel through water for your eyes to achieve proper focus, your vision under these circumstances is actually worse than legal blindness.

If you wear prescription eyewear because you are nearsighted, are farsighted or have astigmatism, you also will need corrective lenses to see clearly underwater.

But your prescription may need to be changed because the distance between the lens of your goggles or diving mask and your eyes is often different from the distance between your eyes and eyeglass lenses. (In fact, this is one of the reasons your contact lens prescription is different from your eyeglass prescription.) An eyecare professional specializing in sports eyewear can adjust your prescription for underwater use.

Your choice of a diving mask or goggles will depend on your activities and specific needs. What to consider:

Tips for Buying Scuba Diving Masks

Diving masks, which are designed for scuba diving or snorkeling, tend to be large and rectangular, rising high and across the forehead and dipping down low, almost to the bottom of the nose. Most diving masks are made of soft silicone, which is hypoallergenic and resists deterioration. Most have a double-flanged (two protrusions) face seal to keep the mask watertight.

Prescription diving masks work in one of two ways:

• The entire lens area is a prescription lens, or
• Prescription lenses are inserted separately between the mask face shield and your eyes.

If the dive mask comes with prescription lenses, it can be made to your specific measurements and correction. Also, masks are available pre-made with prescription lenses that have an equal correction for nearsightedness or farsightedness for both eyes.

Although these pre-made lenses don't correct astigmatism, most people who need corrective lenses can see well enough with them in most underwater situations. But if you have a lot of astigmatism, this solution may not be for you.

Alternatively, some diving masks have a fixed lens area in the front that allows an insert containing custom-made prescription lenses to slide in behind it.

Prescription lens inserts are handy especially for contact lens wearers, because the same diving mask can be used depending on your choice of vision correction. If you wear your contact lenses for a dive, you don't need to use the prescription insert. If you prefer not to wear your contacts, you can slide in the insert for a clear underwater experience.

Keep in mind that not all contact lenses are suitable for diving, and swimming or diving with your contacts can cause problems. Gas permeable lenses (GP lenses) can "dig in" to the eyes below certain depths because of pressure, and soft contact lenses can collect waterborne organisms, become contaminated and cause eye infections. This can happen in swimming pools, lakes, rivers and the ocean.

If you wear contacts, use a mask with a tight seal. Micro-organisms get trapped in contacts and can cause nasty infections. Or wear a prescription mask instead of your contacts. Shown is the Seal Mask from U.S. Divers.

Tips for Buying Swim Goggles

Swimming goggles are similar to diving masks, but they are much smaller and are usually round. They also fit closer to the eyes than dive masks.

Goggles protect your eyes from the water but are sleek and unobtrusive so they won't interfere with your speed and motion. In prescription goggles, corrective lenses are integrated into the watertight silicone frame.

Pre-made prescriptions for myopia and farsightedness that are the same for both eyes are commonly available.

Generally, swim goggles are used in pools, a setting where prefabricated prescription goggles provide adequate vision. If necessary, however, custom lenses — including lenses that correct astigmatism — can be made for any model of goggles. Lenses for diving masks and swim goggles are available in a variety of materials, including glass, acrylic, plastic and polycarbonate.

Ask your eyewear provider for assistance in adapting your eyeglass prescription for use in goggles or masks. Many such providers can point you to companies that will match the scuba masks or swimming goggles you want with prescription inserts. Your prescription must be provided by your eye doctor.

Your regular eye doctor or a sports vision specialist may be able to give you other recommendations.

[Page updated October 2008]