Snorkeling is a very popular recreational activity especially in warm waters around tropical islands. It is very accessible to anyone with little equipment and no required training. Grabbing a snorkel, mask, and fins is the easiest way to explore coral reefs. The simplicity of the activity appeals to many travelers seeking a simpler lifestyle on their tropical island holidays. But how does a snorkel work?

How Does a Snorkel Work?

A snorkel works by letting a person breathe without lifting their head out of the water when swimming face down. Snorkels are accompanied by masks, which allow the person to see and breathe.

There are several types of snorkels. The most basic models are made from rubber or plastic, shaped into a slightly bent tube with a rubber or silicone mouthpiece attached to one end. They are typically about 1 foot or 30 cm long.

The snorkeler first attaches the snorkel to a mask with a snorkel release. There are many varieties of snorkel releases, but many do not keep the snorkel in a good position, get entangled in your hair or fail to keep the snorkel attached altogether. Once the snorkel and mask are attached, the snorkeler swims on top of the surface and is able to breathe through the tube (snorkel) in order to observe the reef without having to lift their head to breathe all the time.

We are not able to simply extend snorkels in length. The pressure increases even and especially at shallow depths won’t allow your lungs to “pull” the air to depth. It is impossible past a certain depth.

Furthermore, even a regular-sized snorkel traps CO2. CO2 trapped in a snorkel is called dead-air space. Inhaling CO2 first, before the fresh air from the atmosphere can enter the lungs. This can lead to an air starved feeling and shortness of breath in extreme cases.

Traditional Snorkels

The most commonly used snorkels are traditional types. They are very cheap and easy to use. Most traditional snorkels are composed of a tube and a mouthpiece. They are light-weight and often made of a rubber or silicone material, making them flexible for easy storing. Scuba divers also use snorkels on the surface and often prefer traditional, low impact and light weights snorkels. Freedivers also prefer traditional snorkels since the sport of freediving is all about reducing the amount of equipment and equipment dependence.

These snorkels require the snorkeler to constantly manage their airway. Often water manages to get into the tube which needs to be cleared. After a breath-hold dive, the snorkeler needs to preserve enough air in order to clear the snorkel on the surface. The tube fills with water upon submersion and the forceful exhale on the surface blasts that water out of the tube.

This requires skill and practice.

Dry & Semi-Dry Snorkels

Dry snorkels feature newer technology built into the snorkel. They typically feature a drain valve situated at the bottom of the mouthpiece. This is a one-way valve, allowing air and water to escape, however no water to enter. This means that airway control is simpler compared to traditional snorkels. The small amount of water that accumulates with ill-fitted mouthpieces can exit the snorkel via the drain valve without the snorkeler having to constantly blow it out.

Furthermore, they often feature a splash guard (semi-dry) or ball valve (dry) at the end of the tube. A splash guard simply prevents most of the water from small waves to enter the tube and fill the snorkel. Whereas a dry snorkel prevents water from entering the tube altogether, even when fully submerged. Once you resurface with a dry snorkel, the valve allows air to flow both ways again. Some newer models allow exhaled air to escape the snorkel each time, reducing the amount of CO2 inhaled each time.

Even a “dry snorkel” however is no guarantee that no water will enter the snorkel. Ill-fitted mouthpieces or a peculiar angle can still allow some water to enter. For beginners, these snorkels make snorkeling much easier. Many people give up on snorkeling because they do not know how to manage their airway effectively and are sick of breathing in lots of saltwater.

Full Face Snorkel Masks

Relatively new on the market are snorkel masks. These seal around the person’s face, allowing easy and continuous breathing through their mouth and nose. Full-face snorkeling masks keep the airways separate to prevent the mask from fogging up. The snorkel component on top is a dry snorkel design in order to prevent flooding of the full face mask.

Beginners are less likely to perform breath-hold dives. This is why full-face snorkel masks are very popular among beginners. It is quite difficult to dive down with the large air pocket trapped near the snorkeler’s face. They do however keep water away from a snorkeler’s airways, which increases comfort for inexperienced ocean explorers. Having to keep a mouthpiece in for extended periods of time causes a lot of people nausea and a feeling that they want to vomit. This deters many people from snorkeling using traditional snorkels and is not a problem with snorkel masks.

These do however take away that nice back to basics feeling of a simple mask and breathing tube. Also, let’s be honest, they look a bit silly.

Snorkeling and Safety

Snorkeling seems so easy and safe. But is it? When asking, how does a snorkel work, let’s consider that it is essentially a tube that you breathe through. A snorkel’s technology does not prevent drowning. Proper training and skill can greatly increase the effectiveness and safety of a snorkel. In fact, snorkeling takes more lives than scuba diving due to its popularity and how easily accessible the gear is. Similar to scuba diving and free diving, snorkelers also set personal limits. How comfortable is someone in water too deep to stand in? More experienced snorkelers or divers should always accompany a new and inexperienced snorkeler. It is many people’s first entry into the underwater world and it should be an enjoyable one.

Read Do You Need to be Certified to go Scuba Diving?


How does a snorkel work? Well, it really depends on what type of snorkel you use. However, they all provide air through a tube that is inhaled via the mouth. Snorkeling is often a gateway experience to scuba diving and free diving. In fact, it requires a decent amount of skill to do well, especially when duck diving down in order to get closer to the reef. Snorkels are a wonderful and easy way to start exploring the ocean.