Full-Face Snorkel Mask or Center-Mount Snorkel: An In-Depth Comparison

When choosing gear for underwater activities like snorkeling or for dedicated swim training, you'll encounter two common options: full-face snorkel masks (FFSMs) and center-mount snorkels (CMSs). Both allow breathing with your face submerged, yet they are designed for distinct purposes and have unique features. This article will explain their designs, typical users, benefits, drawbacks, and key safety points to help you decide which is more suitable for you.

The Full-Face Snorkel Mask (FFSM): A Wide View of the Water

A lot of people, especially those who swim for fun, now wear full-face snorkel masks. They let you see and breathe underwater in a new way.

Key Design Features

The FFSM is a single item that includes both the mask and the snorkel and covers the whole face. Its wide lens, which often gives you a 180-degree view, is one of its best features. This means that you can see the whole underwater scene without a mask frame getting in the way.

Better FFSMs have different channels for breathing in and breathing out. The snorkel tube lets in fresh air, and different vents let out expelled air that is high in CO2. The goal of this design is to cut down on fogging and, more importantly, the risk of taking in old air again. Most of them also have a "dry top" snorkel. This is a device, usually a float or valve, that closes the opening of the snorkel tube if it goes underwater, keeping water out. The mask is held on to the head by straps that distribute pressure for a snug fit.

Who Are FFSMs For?

FFSMs are mostly made for people who are just snorkeling on the top in calm water for fun. People who are just starting out or who find the opening on regular masks and snorkels uncomfortable like these. People who want a wide view and the ability to breathe through both nose and mouth, like on land, like them. This makes them a good choice for people who are just starting to explore underwater.

What Are the Benefits?

The main benefit of an FFSM is the wide field of vision. The large lens gives you a panoramic view that you don't get with older masks. Many people also find it more natural to breathe through both their nose and mouth.

Other advantages include:

• Dry Top System: These generally work well to keep water out if the snorkel dips under.
• Less Jaw Fatigue: You don't have to bite a mouthpiece, which can make your jaw sore.
• Easier for Beginners: They can be simpler to use for people new to snorkeling.

Downsides and Safety Risks

While FFSMs can be useful, they also pose some safety risks that users should be aware of. CO2 growth is the main worry. If a mask is poorly made, doesn't fit right, or has a problem with its breathing system, air that you breathe out can build up inside it. Rebreathing this air that is high in CO2 and low in oxygen can make you feel dizzy, give you headaches, make you confused, or even make you lose consciousness. This risk goes up when you work out and breathe faster.

One big problem is that you can't balance the pressure in your ears. If you want to avoid getting ear pain (barotrauma) when going down even a few feet, pinch your nose and slowly let out your breath. With an FFSM on the face, this move can't be made. Because of this, FFSMs should only be used on the surface and not for any kind of diving, even short dives.

The Center-Mount Snorkel (CMS): A Tool for Swimmers

How it's made and what it's used for are very different between the FFSM and the center-mount snorkel. It's mostly used by swimmers to train.

Key Design Features

When using a CMS, the breathing tube goes from the forehead to the mouth and is right in front of the face. The only way to breathe is through the mouthpiece. A head strap or clip that is padded at the forehead keeps the helmet stable. A CMS doesn't cover the eyes like an FFSM does, so you need to wear different swimming goggles. Most snorkel tubes have an open top, but some types may have a splash guard to keep some water out.

Who Uses It?

A CMS is almost always used to learn and improve swimming technique. A lot of competitive swimmers, exercise swimmers, and triathletes do it as part of their workouts. Its main goal is to let swimmers focus on body position and stroke patterns without having to turn their heads to breathe, which is especially helpful for freestyle.

What Are the Benefits?

Using a CMS can help swimmers in several ways:

• Improved Body and Head Position: Promotes a still, downward-looking head position for better body alignment in the water.
• Focus on Stroke Technique: Allows concentration on arm movements (catch, pull, recovery) and kick, without the interruption of turning to breathe.
• Symmetrical Stroke Development: Helps prevent imbalances that can arise from consistently breathing to one side.
• Reduced Neck Strain: Eliminates the need for repetitive head turning, which can strain the neck and shoulders.
• Consistent Airflow: Enables the development of a steady, rhythmic breathing pattern.
• Effective for Drills: Complements various swimming exercises and drills designed to isolate parts of the stroke.

What Are the Drawbacks?

There are a few things to consider with a CMS:

• Mouth Breathing Only: Standard for snorkel use, but may require some adaptation for those not used to it.
• Requires Separate Goggles: This means an additional item of equipment to purchase and manage.
• Limited View for Sightseeing: Goggle vision is more restricted than an FFSM's panoramic view, making it less ideal for observing surroundings.
• Adjustment Period: It may take some time to get comfortable with the breathing pattern and the technique for clearing water from the tube.
• Potential for Water Entry: The open top can allow water in, especially in choppy conditions, though experienced users can typically clear it with a forceful exhale.

Which One Should You Get: FFSM or CMS?

Choosing between an FFSM and a CMS really comes down to what you plan to do and your comfort with the equipment, keeping safety in mind. The pros and cons we've just discussed should guide your decision.

Reasons to Get an FFSM

An FFSM might be a good choice if:

• You're a casual snorkeler who will only be on the surface in calm, shallow water.
• A very wide view is important to you, and you like the idea of "natural" breathing.
• Traditional mouthpieces bother you.

Most importantly: You understand the CO2 risks and how to reduce them (buy from good brands, stay in calm water, don't overexert yourself, never snorkel alone, and know the warning signs).

Reasons to Get a CMS

A CMS is likely better if:

• You want to improve your swimming technique and efficiency in a pool or similar setting.
• You're a lap swimmer, competitive swimmer, or triathlete.
• You want to reduce neck strain during swim workouts.
• You're fine with breathing only through your mouth and using separate goggles.

When to Avoid FFSMs and CMSs

• AVOID FFSMs for: Any kind of diving (because you can't equalize), hard swimming, if you're alone, or if you have breathing problems. The risks are too high in these situations.
• AVOID CMSs if: Your main goal is to leisurely look at underwater scenery and you want a wide view.

Important Safety Reminders

No matter what gear you use, safety in the water always comes first.

FFSM Safety Checklist

• Research Brands: Choose FFSMs from known companies that test their products for safety, especially airflow.
• Proper Fit: Make sure it fits well to prevent leaks and to help the breathing system work correctly.
• Calm Water Only: Best for calm conditions. Avoid rough water or strong currents.
• Never Snorkel Alone & Supervise Kids: Always have a buddy. Kids using FFSMs need constant, close adult supervision.
• Know CO2 Symptoms: If you feel dizzy, headachy, short of breath, or very tired, take the mask off right away in a safe spot.

CMS Safety Checklist

• Good Goggle Fit: Leaky goggles are distracting.
• Practice Clearing: Learn to give a sharp puff of air to blow water out of the tube.
• Get Used to It Slowly: Try it in a pool first and for short periods.

Beyond the gear, always be aware of your surroundings and the water conditions. Know your limits and don't push them. If you're going into open water, tell someone where you're going.

Outfit for Your Water Needs!

Neither the full-face snorkel mask nor the center-mount snorkel is the "best" for everyone. They're tools for different jobs. The FFSM can be easy to use and give a great view for very casual surface snorkeling, as long as you take the safety warnings about CO2 and equalization very seriously. The CMS is a training tool for swimmers wanting to improve. Think about what you'll be doing, put safety first, and that will help you decide on the right equipment for your time in the water.