Connect with us

Diving Safety

Listen Up: Freediving is About to Enter a New Era if Oxama has a Say!

Now, just like their triathlete counterparts, freedivers will be able to access their realtime biometric performance data, including heart rate and blood-oxygen saturation, enabling them to fine-tune their performance, thanks to an Italian start-up called Oxama. What’s more, the device, which links to your smartphone, uses an innovative audio interface, enabling divers to geek out on their metrics, hands-free. Fortunately, adventure writer and photographer Florine Quirion caught up with the Oxama team. Here’s what they had to say.



by Florine Quirion. Header image by Lorenzo Mittiga. Photos and video courtesy of Oxama.

The current tech craze inspires rapid hardware development in many industries, including recreational scuba and tech diving. However, tech innovators have seemed to skip over freediving—until now. In mid 2022, Oxama will introduce an audio freediving computer. 

In 2019, Claudio Mattavelli, Massimo Moi, and Vincenzo Palumbo founded Oxama, an Italian start-up. The three passionate freedivers from Milan define their computer as a virtual vocal coach that “tracks your freediving experience.” The team took naming inspiration from blood oxygen saturation (Ox) and the name of pearl divers in Japan (Ama).* They ran a Kickstarter campaign at the end of 2021, gathering 60% more than their initial objective of €15,000. 

We met virtually with Massimo, Oxama’s COO, for an exclusive interview following their successful campaign. Let’s dive into how Oxama is going to change the freediving world.

*A quick check with Urban Dictionary paints another picture. Oh those Italians!

Massimo, tell us a bit about yourself… you have been freediving for decades; how did you start, and how has your diving changed over time?

I started freediving at a young age with my dad in Italy in the 1980s. In the Mediterranean Sea, spearfishing is a common tradition, and we used to spend summer vacations spearfishing for hours in the waters of Liguria and Sardinia. We had so much fun that we often lost track of time, even though.  At that time, all we had was one mask and two fins. 

Later, in the 2010s, I started formal freediving training in a pool. I met Claudio [Mattavelli] and Vincenzo [Palumbo] in 2016 while I was training. The first freediving wrist computers had appeared only a couple of years before, and only recently did  that technology get involved in freediving. But despite a handful of brands releasing specialised freediving computers, none of them ever considered biometric data.

How did you come up with the idea for the Oxama freediving computer?

I didn’t have a dramatic wake-up call underwater, but I began to feel a profound desire to improve underwater safety. At the beginning of 2017, Claudio, Vincenzo, and I were preparing for our next summer trip. During our pool training, we realised there should be a way to improve our underwater preparation. 

We searched for new exercises that would extend our physical abilities underwater, which led us to conclude that we needed to track how our bodies reacted to these exercises to optimise our results, and the initial idea for Oxama was born. We wanted to better understand the link between our physiological parameters and how long and how deep we could stay underwater. We officially started the Oxama project in 2019. Today, our first version can track eight parameters: heart rate, blood oxygen saturation, head angle, speed, acceleration, depth, and time.

Freedivers wear the Oxama computer on their face—below their mask—allowing them to hear their parameters. Could you explain a bit more about how it works?

Data analysis of a deep dive at Y-40 (see details below)

Before the dive, the diver, relaxed, has an heart rate (HR) around 60bpm but during the ventilation it rises up to 90bpm due to the intense respiratory effort. The dive begins and, with a constant speed of -1.3m/s and an almost perfect vertical head posture of -83 degreee, the diver reaches the bottom of the pool at -42m. The HR drops down and, after a static rest of 60 seconds, it reaches the minimum of 52bpm due to the diving reflex. The blood oxygen saturation (Spo2) remained between 97 and 99 % during all the descent, and it starts to decrease when the ascent begins. During the ascent, the speed is about 1.0 m/s, the head posture between 70 and 90 degrees, the HR increases up to 100bpm at the surface. The SpO2 decreases during all the ascent and touches its minimum of 85% as the breath holding end, then quickly increases up to 90% in few seconds as the ventilation starts. In next 30 second, the divers recovers and HR comes back to the basal value of 70bpm and the SpO2 to 99%

The idea is based on bone conduction, which carries sound vibrations through the bones of the skull and inner ear. With audio-based information instead of text on a monitor, freedivers can access their underwater performance stats without having to look at their wrists. The computer includes a bone transducer encased in a soft silicone mask. Using bone conduction instead of earphones, the transducer generates a human voice and communicates the audio via sound vibrations that travel through the skull and inner ear, which the eardrums perceive as audible sounds.

Vincenzo came up with the high-tech idea. We are lucky to have an experienced optic quantum physicist on our team! He started experimenting with simple pulse oximeters found in pharmacies. Then, he had this breakthrough idea to avoid interrupting  freedivers’ concentration. 

Divers, without the need to read a computer on their wrists, can maintain the best dive position at all times. Freedivers can keep their bodies streamlined without losing focus on their sensations. 

Can beginners and competitive freedivers use the Oxama computer differently?

All freedivers (beginners or athletes) can set Oxama to different modes. They can choose the parameters and the exact moment when to listen to the recorded values. The Oxama computer currently has four audio modes: quiet, alert, chatty, and mute.

As a virtual coach, Oxama can help beginners better understand their own physical limits. This is when the blood oxygen saturation information is most helpful. The Oxama computer gives the beginner the information they need to start freediving safely in a controlled manner.

In the case of competitive divers, some of the most valuable parameters are the ascending and descending speed and the head angle. With these parameters, divers can improve their performance by pinpointing their own improvement benchmarks.

Could you give us more details about how Oxama measures  blood oxygen saturation and heart rate?

With Oxama situated on the freediver’s face, the computer has close access to facial blood vessels. Our patented technology exploits the optical properties of blood flow to determine blood oxygen saturation and heart rate. The facial artery’s lateral nasal branch—on the side of the nose—is an excellent point of measure. Like a pulse oximeter measures oxygen saturation and heart rate from the blood vessels of the fingertips, Oxama can do the same on the face.

However, there is another benefit to taking measurements on this part of the body. As freedivers descend deeper, their blood moves from their peripheral limbs towards the inner body, and vasoconstriction occurring at deep depth makes precise measurements at the finger or wrist extremely difficult. Hence, the face is an excellent location to measure the blood metrics no matter the depth.

Since divers can access all of Oxama’s data on their smartphones, what are your tips for interpreting the data to extend dive time? Have you found any interesting observations so far?

With data graphs, freedivers can understand how and where to improve their dive time. The blood oxygen saturation and heart rate data are significant indicators—they show divers where they need to improve both concentration and relaxation to reduce their physical strain. Physical effort saps the limited supply of oxygen divers took at the surface. Oxama also uses it to recommend a recovery time between dives. This is a fantastic way to track their general fitness development over time, as well.

During the first phase of testing, our team noticed that their oxygen saturation remained constant for the entire  descent period and decreased during ascent in the final meters. In the same way, their heart rates remained constant throughout the descent and then began to increase during the ascent.

Another interesting observation was the impact of the head angle in ascent and descent—the more aligned with the rest of the body, the better. By not requiring divers to look at a computer on their wrists, Oxama helps them maintain optimal alignment. The same applies to descent and ascent speed which need to be as consistent as possible to maintain energy efficiency. 

When will free divers be able to try Oxama computers in 2022?

Our goal is to launch the Oxama freediving computer in July 2022, when, hopefully, freedivers will be able to buy it from our website. We are also currently negotiating retailing deals with dive shops in Italy before expanding globally.

To that aim, we have started organising test sessions in diving pools. In mid-February, we will do a session at the Y-40 deep pool in Padova, Italy, with its technical director, Marco Madollo. We want to repeat the test in March 2022 with free diving athletes.

Dive Deeper

InDepth: The Making of the Biometric Diver: DAN Europe’s Alessandro Marroni is Realising a 50-year old Dream

To explore additional stories, videos and webinars on freediving click: FREE

Florine Quirion is a writer, underwater photographer, and dive travel blogger at World Adventure Divers. She dives in tropical to extreme cold waters and selects destinations where adventurous diving and cultural discoveries are a part of the journey.

  • Halcyon Sidemount
  • Subscribe for free
  • Area 9

Diving Safety

Who You Gonna Call (in an Emergency)?

In the immediate aftermath of a diving fatality, law enforcement needs to locate an emergency contact for the accident victim. If that person’s phone is locked, social media accounts private, and there’s no emergency contacts for friends or family, it will likely fall to you as a dive buddy, to locate the needed critical information. This can add unbearable stress to an already bad situation. The solution is to be prepared, as Buck Buchanan and Wally Endres with Christine Tamburri and Robert Zink explain.




by Buck Buchanan and Wally Endres with Christine Tamburri and Robert Zink. Images courtesy of the authors unless noted.

According to the 2020 DAN Annual Diving Report, 189 diver fatalities were reported in 2018 across all categories, including recreational, technical, breath-hold, commercial, public safety, and military diving operations. There were 228 diver fatalities reported in 2017. Despite the 17% decrease in fatalities from 2017 to 2018, divers are still dying and there is a lot to learn from these incidents.

Dive accidents happen, not only to reckless divers, but also to the most cautious, most well prepared, most highly trained divers in the world. While we may not want to think about it, the reality is that dive-related emergencies can happen at any time to any diver on any dive. Because of this possibility, all divers should be proactive in their efforts to mitigate the effects of chaos and confusion being added to those of shock and grief. 

Whether a diver experiences a minor injury or is the unfortunate victim in a fatal accident, the need for easily accessible and reliable emergency contact information is crucial. This article dives into the importance of such precautions as well as provides specific tips for how to carry them out.

Why is Emergency Contact Information (ECI) important?

Imagine you and a buddy are on a weekend diving getaway. You could be in your home town or half-way around the world. Nevertheless, the sun is shining, the water is crystal clear, and all is well with the world. Soon after submerging, tragedy strikes, and your buddy—maybe even your best friend—never resurfaces. Suddenly, your perfect day has changed your life forever. What happens next can be handled either efficiently or chaotically, depending on the emergency contact information (ECI) on hand.

In the immediate aftermath of a tragedy, law enforcement needs to locate an emergency contact for the accident victim. If that person’s phone is locked with no known passcode, their social media accounts are private, and nothing in their wallet or on their dive gear points to any ECI for friends or family, you as the dive buddy, will need to help locate critical information. Doing this, while dealing with your own shock, adds almost unendurable stress.

Law enforcement’s primary role in any fatality investigation is to secure evidence, to identify the victim, to determine cause of death, and to make proper notifications to next-of-kin. This standard process changes in most, if not all, diving accidents that result in a death because most law enforcement agencies are either ill-equipped, untrained, or unaccustomed to handling a diving fatality. 

  • Halcyon Sidemount

Consequently, the more identifying information available, the easier it is for law enforcement to be effective. It should also be noted that most law enforcement agencies are not equipped to properly secure an underwater crime scene or to recover a deceased diver at depths. 

ECI is a crucial piece of documentation. When a victim is seriously injured or dies, the need to contact someone in their network is necessary to initiate the next steps in the process. These steps may include providing a medical history to help EMS respond accordingly, arranging transportation home from a remote dive site, and/or notifying loved one(s).

Without ECI, an injured diver may be left on their own for hours. In cases where they are unable to advocate for themselves, medical professionals may be forced to make uninformed decisions for care. In the unfortunate case of a fatality, the lack of accessible ECI may mean that families are unaware for hours, days, or even weeks, not knowing the fate of their loved one.

Planning ahead and ensuring that ECI is available is part of “getting our affairs in order.” Divers should make available all vital information needed to assure that their loved ones will be reached in a timely manner.

Smart Emergency Stickers by Dive Signs (see information below)

Emergency Contact (Point of Contact) vs. Next-of-Kin

An emergency contact can be a close friend, a relative, a co-worker, a neighbor, a dive buddy, a mentor, a pastor, or other trusted persons in your life. Remember, naming an emergency contact is not to be taken lightly. This is the person that will be contacted in the event of an unexpected, life-changing event, and often this individual will be the one tasked with informing other people close to the accident victim.

A next-of-kin contact is the closest living relative to the injured or deceased. In some cases, this person may have legal authority to make decisions.

It is important to understand the difference between these two terms so that a diver can choose who to list as their emergency contact. News of this nature is very traumatic for all loved ones, especially significant others. Certified divers understand the inherent risks that they are taking. Even if family members who are not divers think they understand the risks, the shock of losing a loved one is devastating. It may, however, be less traumatic if that horrible news comes from someone familiar to them. For example, the diver may choose to list their best friend as their emergency contact, knowing that a friendly face can soften the tragic news. With this information available, law enforcement would notify the listed emergency contact, and that person would notify the spouse or close loved one. 

In the event that there could be estate or legal implications, the decision to use next-of-kin as the emergency contact should be considered carefully.

  • Area 9

The More Information the More Efficient

The Emergency Contact

After deciding who is to be listed, it is critical to obtain their most up-to-date contact information. At minimum, the following information should be listed and easily accessible:

  • Full Name of the Person to be Contacted
  • Relationship of the Person to be Contacted
  • Phone Number(s) of the Person to be Contacted

In addition, it is recommended that the following information also be included:

  • Email Address of the Person to be Contacted
  • Full Street Address of the Person to be Contacted

The more information available, the easier it will be for medical staff or law enforcement to understand the full scope of the relationship between the injured individual and the emergency contact. 

Personal Information

It is important to remember that a situation does not instantly resolve when an emergency contact is reached. All divers should be proactive in their approach to ensure that medical staff and law enforcement have quick and easy access to not only ECI in the event of an incident, but to personal information as well. The next section discusses ways in which to house these details but, at minimum, the following personal data should be accessible:

  • Full Name
  • Date of Birth
  • Phone Number
  • Email Address
  • Full Street Address
  • Primary Care Physician Contact Information
  • Pertinent Medical History (i.e., Known Allergies, Recent Surgeries, etc.)
  • Blood Type

Solutions for All Divers

Gathering ECI and personal information are just two steps in the process of preparing for the event of a dive accident. To be of value, these pieces of information must be easy to obtain quickly. Divers need to be aware that, for their buddies and fellow divers, being unable to contact someone close to an injured or deceased diver is the last place they want to be in the aftermath of a traumatic experience.

These following lists are not comprehensive, but represent simple solutions that all divers can start using TODAY to ensure their ECI and personal information are able to be accessed at a moment’s notice.

Emergency Contact Options

Smartphone Emergency Contact Features (Apple/Android) 

Both platforms offer many features that typically include emergency access to a medical ID in the event that the owner becomes incapacitated. Although most people are unaware that this is available, in most cases, a quick internet search will give easy setup guidance.

To configure an iPhone with a Medical ID, follow these steps on Apple Support . To configure an Android with Emergency Contacts, follow these steps on Android Police.

Visible Gear Solutions 

Divers love to label their gear for a number of reasons, but very few make their ECI easily accessible by adding it to their kit.

Duct Tape/Vinyl Tape

Some divers put a piece of tape on their backplate, canister light, or even cylinders that lists emergency contact information. This solution is fast, easy, and cheap.

Dog Tags

Dog tags can be attached to a backplate or sidemount harness, or even tucked into a set of wetnotes. These typically contain ECI, as well as one or two pieces of personal information (i.e., blood type, allergies, etc.).

Smart Emergency Stickers by Dive Signs 

Technology buffs will love this commercially available option. Dive Signs has created a sticker that can be placed on any non-metal surface, such as on a dive crate, on a certification card, or maybe even on a drysuit bag, and it contains a near field communication (NFC) tag. With one tap of a smartphone, anyone can have access to pre-filled emergency contact and personal information that can be easily programmed by the diver. They can be purchased here: Smart Emergency Stickers


Divers constantly need to communicate underwater. Most use hand signals, some use slates, but a common tool is wetnotes. ECI can be written on the first page for easy access after an incident.

Save-a-Dive Kit Solutions 

In similar fashion to labeling dive gear, duct tape/vinyl tape can be put on the inside lid of a save-a-dive kit to list ECI. As an alternative, a printed or hand-written list (preferably laminated) can be used. It should be noted that this method likely won’t do any good if the dive buddy doesn’t know it exists and its location.

State-Specific Databases 

These opt-in systems are put in place for law enforcement in the event of an emergency and they are typically linked to a driver’s license. At this time, these services are only available in a few US states, with Florida having over 19 million participants.

Personal Information
Fillable Form

The following form can be filled in, then printed and placed in a known location so that it is easy to access in the event of an emergency.

You can download the form here: Dive911 ECI Form

Hand-Written List 

The most basic form of documentation, this is easy to add to a save-a-dive kit, in the console of a car, or in another secure location. This list can also be printed and laminated so that it is durable and easy to read.

Emergency Binder 

Some divers may opt for advanced directives that provide instructions for medical care and only go into effect if the injured diver cannot communicate their own wishes. An emergency binder may contain additional information, including passwords, financial and insurance information, a will, and/or government documents such as a passport and social security information. If this route is taken, it is important to understand who has access to this information and when it is invoked. 

ID Tag 

The Divers Alert Network (DAN) Medical ID Tags offer divers an easy way to display important information that may help medical personnel respond quicker and more effectively in the event of a dive emergency. An ID tag displays a diver’s name, DAN ID number, date of birth, drug allergies, and an emergency contact. This information can help public safety officials make informed decisions about their care, even if they are unable to advocate for themselves.

Provided by Divers Alert Network

Best Practices

Each individual diver will have their own method of listing an emergency contact and ensuring their personal details are comprehensive and accessible. Some divers may use suggestions from the lists above, and some divers may design their own ways of housing this important information. Regardless of the documentation method, there are three important points to remember:

List More than One (1) Emergency Contact

Life happens, and sometimes even the most reachable individual is away from their phone, so it is important to list more than one emergency contact.

Update Information when Anything Changes and Review on an Annual Basis

Information is only useful if it is kept up-to-date. Any time information changes, it should be updated on the emergency contact sheet or a personal information list. It is also good practice to review all information on an annual basis to ensure that it is accurate. An easy way to remember to review this information is at the same time as an annual cylinder visual inspection. In addition, the diver should ask their emergency contact to update them with any changes they might have.

Never List a Dive Buddy as an Emergency Contact

This one may seem obvious, but on any given day, one dive buddy has the other listed as an emergency contact. Unsurprisingly, this becomes useless if either buddy has an incident on the dive. As such, it is best practice to list someone who is never a dive buddy as an emergency contact and, again, to verify and update both your and their details.

No one expects an accident to happen to them.The fact is that even the most cautious diver may one day find themself in the middle of an incident, needing quick access to emergency information. All divers are encouraged to be proactive and to ensure that ECI and personal information are accurate and readily accessible. Making a conscious effort during all pre-dive briefs to discuss where and how to access ECI in the event of an emergency is good practice. 

 Photo courtesy of Tom St. George.

This article is dedicated to Ben Strelnick (NREMT, W-EMT) who died on May 26, 2023, while cave diving at Jackson Blue Spring in Marianna, Florida. He was a medic at Divers Alert Network (DAN), and was an avid diver who always put others before himself. The inspiration for this article was drawn from the lack of ECI following Ben’s death and the hardships that followed. Ben wanted nothing more than for people to dive and to do it safely, and he would without a doubt encourage others to plan ahead so that their future dive buddies, friends, and family could get through any type of tragedy with as little pain as possible. 

About The Authors

Buck Buchanan
Wally Endres
Christine Tamburri
Robert Zink

Buck Buchanan and Wally Endres (NREMT, DMT) are co-owners of Dive911, LLC, a Central Florida-based dive training facility that specializes in instructor professional development and public safety pedagogy. Buck is an SDI/ERDI Instructor Trainer Evaluator and Ambassador who has 35+ years of experience in teaching, commercial diving, and heavy salvage. Wally is a Course Director, Public Safety Instructor, and former law enforcement officer who has 25+ years of experience in risk management operations and OSHA compliance consulting. Christine Tamburri (SDI Instructor) and Robert Zink (former law enforcement officer and crash reconstructionist) were also consulted in the composition and viewpoints of this article.

  • Area 9
  • Subscribe for free
  • Halcyon Sidemount
Continue Reading


WordPress PopUp Plugin