Frequently asked questions

General information

O’Dive is a patented breakthrough innovation that allows divers – for the first time in the world – to personalise their diving procedure considering the circulating microbubbles detected post-dive in their venous system.

O’Dive is complementary with the dive computer, that calculates the decompression stops based on the dive parameters and the breathed gases only. In addition to these parameters, O’Dive is measuring the impact of the diving procedures on the diver through a post-dive detection of circulating microbubbles in the subclavian vein.

For a ‘standard’ 30-minute dive at 30 metres carried out using air, decompression stop lengths proposed by primary dive computers range from 12 to 21 minutes in the standard configuration. This variability is even increased when considering all the possible settings (intensification).

Following the post-dive measurements made with the sensor and using the dive parameters manually provided or imported, O’Dive provides a quotation about the diving practice quality with an index (IQ) set between 0 to 100%. The higher the IQ index, the lower the probability of decompression sickness – and vice versa.

Divers can also access a simulator to visualize a posteriori the added value of several options on their practice, such as: increased length of the last decompression stop, oxygen breathing during the stops, nitrox diving, – following options are only available with O’Dive TEK: bottom or step PO2 adjustment, GF values change, diluent gas variation according to the type of dive (OCR, CCR).

In short, O’Dive helps divers to rationalize their diving practice, to improve their self-knowledge and consequently to better their safety towards decompression sickness.

O’Dive sensor detects post-dive circulating gas microbubbles in the diver’s venous system. The measurement is carried out using an ultrasound sensor. The signal is recorded and transmitted hereafter on a server to be analysed.

The amount of microbubbles detected is used to calculate the dive quality index (IQ). This index takes into account the flow of microbubbles detected post-dive in the subclavian vein as well as the dive parameters.

There is a scientific consensus on the fact that the measurement of bubbles in the frontal cardiac region post-dive is of interest in terms of prevention due to its Negative Predictive Value (heightened NPV).

In other words, the absence of microbubbles in the diver’s venous system post-dive represents better decompression quality. The O’Dive system was created on the basis of this result.

Studies have shown that at the scale of an individual and an isolated dive, the presence of microbubbles post-dive is not synonymous with significantly increased probability of sickness (low PPV) in relation to all susceptible intervening factors in the origin of DCS.

On the other hand, at the scale of numerous dives spread over time and for a given engagement (depth/length), studies based on professional databases* have brought to light the existence of a significant risk ratio between dives that have led to high bubbles’ grades and dives that have led to low bubbles’ grades.

* “Reliability of VGE detection in subclavian area for decompression stress assessment following scuba diving” J. HUGON, A. METELKINA, A. BARBAUD, R. NISHI, F. BOUAK, E. GEMPP, JE BLATTEAU Diving and Hyperb. Medicine Journal, Vol. 48 No. 3 – Sept. 2018

O’Dive has been developed over a number of years in order to adapt to the physiology of the majority of people. The acoustic cell in the sensor’s core has been specially developed to enable the measurement of blood flows in the subclavian vein.

However, human physiology is such that for some individuals, the perception of bubbles is impossible due to the vein being too deep or offset in relation to the clavicle, for example.

In the event of difficulties in receiving a good signal, the O’Dive teams will do all they can to check whether this is due to poor positioning of the sensor, technical issues, or a physiological issue preventing measurement. In the latter case, the client will receive a full refund.

In any eventuality, the teams at Azoth Systems are dedicated to resolving any difficulties experienced and to reducing physiological issues by researching corrective solutions.

Decompression sickness is of a statistical nature.

The risk of decompression sickness can be modelled in a simplified way, using a combined result of the following components:

  • dive severity (depth-length ratio of the dive, resurfacing duration, sequence and quality of respired gas)
  • suitability factor of individuals’ procedures (which can be assessed by the absence or quality of vascular gas microbubbles potentially detected post-dive)
  • medical factors

Risk = (dive severity) x (degree of suitability of procedures) x (medical factors)

Divers determine the first component themselves when selecting their dive settings.
O’Dive provides divers with an indication on the second component.
O’Dive is in no case linked to the medical aspect of diving, which relates solely to medical professionals.

On the basis of projections carried out using professional data, divers producing the highest amounts of bubbles who comply with O’Dive’s recommendations are likely to improve their technique and see the risk of sickness linked to their technique significantly reduced.

However, sickness will unquestionably continue to occur and O’Dive will be unable to prevent it from occurring deterministically.
Statistical improvement of safety conditions alone is likely to occur, resulting from previously listed components.

By definition, all measurements made within the time interval contained between 20 and 90 minutes post-dive are of use to the system, with preferential times for carrying out measurements being T0+30 minutes for the first one and T0+60 minutes for the second (T0 signifying the time at the end of the dive).

Azoth Systems presentation

O’Dive is the product of Azoth Systems’ latest developments, in which we put our expertise of professional diving to use in the world of recreational diving.
For 10 years, Azoth Systems has been providing assistance to professional divers across the world – businesses, industrial groups, actors in the defence field – in order to improve decompression sickness prevention.
Our expertise is founded on individual skills, partnerships with institutions, state-of-the-art laboratories and Ministries of Research and Defence.

Using the sensor

A simplified user’s manual is provided with the product that you have just received. This manual describes the steps to be followed to use the sensor properly.

Three steps are crucial before any use of the sensor post-dive:

  • downloading the O’Dive ONE or O’Dive TEK app on your smartphone (or on the device you will use to make the measurements)
  • creating your personal account on the app
  • watching the tutorial available on the app (in the ‘Tutorial’ section). The proper positioning of the sensor and diver’s posture during the measurements are essential for a good signal quality and service delivery. Thus, it is necessary that all divers using O’Dive product have watched this tutorial or have been trained in its use.

Finally, it is highly recommended to perform the first measurements with a mirror to be able to properly visualise one’s clavicles and position the sensor.

The simplified manual explains step by step how to use the sensor. If you are facing any difficulty, do not hesitate to contact the customer service and describe the problem by email (contact@o-dive.com) or over the phone.