COBRA extends the supply of emergency breathing gas for subsea operations

Jon Lawson

Danny Gray discusses the key drivers for keeping the industry afloat

Operating out of sight, often isolated and in a dark and cold environment, commercial divers work in some of the most dangerous and extreme conditions of any industry. They conduct complex operations even in the most hostile of settings, facing a plethora of potentially life-threatening risks. For this reason it is vital that HSE (Health Safety and Environment) is the primary focus for every organisation and corporation throughout all operations, and that divers have the utmost confidence in the safety standards applied to all work carried out in a subsea environment.

Given today’s economical challenges, many divers operate as contractors to a range of companies and in a variety of regions, rather than as permanent employees to one company. As a result of this, safety provisions and emergency procedures can differ for individual operations. Whether through accident or circumstance, the risks associated with any incident when operating subsea are of the highest degree and cannot be overstated.

Reliable contingency measures need to be in place that cover all aspects of a safe rescue operation. This encompasses all stages of safely returning divers to the shore, from the provision of an emergency gas supply through to safe decompression.

Divers are experts in their field and are trained to instantly recognise any signs of danger that may pose a risk to their lives or the lives of their fellow divers. However, the ability to successfully act upon these warning signs and conduct a safe rescue is almost entirely dependent on the capability and reliability of the equipment they are using, as well as the technologies they apply to provide the necessary contingency measures, should there be an incident.

Regulatory environment

Regulatory requirements for the supply of emergency breathing gas vary depending on the governing body and the regions in which the divers are operating. In addition, considerations need to be made for the conditions that will impact the supply of emergency breathing gas, in particular operating depth. Even where there is a more stringent regulatory requirement for the minimum supply of emergency breathing gas, such as under NORSOK or IMCA D024 standards, it is not reflective of the technological capability available in the market today.

Until now the industry standard for the provision of emergency breathing gas has been limited to just a few minutes, depending on the method employed and the diver’s operating conditions. This poses a significant risk, particularly when working in extreme conditions. Indeed there have been incidents that have resulted in a near-miss and could easily have become a fatality due to inadequate emergency breathing gas supply. It is a critical industry challenge that cannot be left unmet.

In line with this, and as a direct response to the urgent need to drive significant improvements in safety standards, JFD developed the compact bailout rebreathing apparatus (COBRA) rebreather set, which provides an advanced emergency bailout provision that greatly extends the supply of emergency breathing gas, providing a supply of up to 33 minutes at a depth of 120m. Compared to conventional bailout methods such as the seven litre 300 bar twin scuba set, which at 120m provides seven and half minutes of breathing gas (based on a consumption rate of 40 litres per minute), the advanced technology of COBRA is a step forward in improving subsea safety.

JFD recently delivered six COBRA sets to Rever Offshore (formerly Bibby Offshore) to enhance diver safety. Since delivery the company has successfully completed the first deep test dives in the North Sea. Rever Offshore is the first North Sea contractor to adopt COBRA, thereby setting a precedent for diver safety in the region. The technology is expected to be adopted by a number of other North Sea contractors as part of the continual drive for improved safety standards.

The technology and capability exists in the market today to provide an extended emergency gas supply that will allow divers the best possible chance to get themselves to safety in the event of an incident that could threaten their lives. It is essential when undertaking operations of any nature or in any region that divers have the confidence that the companies they are working for will ensure the provision of a reliable, advanced emergency bailout rebreather capability that will provide absolute assurance that they can conduct their operations in the safest conditions possible.

Once the diver has left the diving bell they are reliant on their primary rebreather function, with the emergency gas supply readily available as a contingency measure to allow them to return safely to the bell. However, this is one scenario and just one stage in the recovery process.

Saturation diving support vessels (DSVs) require a rescue contingency for their divers in the form of a self-propelled hyperbaric lifeboat (SPHL). In the event of an emergency evacuation, hyperbaric lifeboats accommodate saturation divers for up to 72 hours using on-board life support, during which time the vessel is transported to a facility where the divers can be safely decompressed.

JFD has supplied over 135 integrated and modular saturation diving systems to clients around the world. Through a recent joint venture alongside Singapore-based lifeboat manufacturer Vanguard, JFD has increased its capability to deliver a new generation of SPHLs that greatly improve the chances of the safe recovery and decompression of the divers. JFD has developed a range of advanced SPHLs for the commercial diving industry that combine proven, high quality internal chambers and life support equipment with specialist hull construction, ensuring there is a robust and reliable emergency evacuation at pressure contingency in place.

In the event that the SPHL has to be deployed from the DSV and has reached a safe haven, the divers are still at great risk of serious health complications or even fatality if they do not undergo a decompression process to gradually return their bodies to atmospheric pressure.

Safe decompression requires the capability of a full hyperbaric evacuation system (HES). A key part of this is a hyperbaric rescue facility (HRF) that can safety transfer rescued divers at pressure and deliver them to a hyperbaric rescue centre (HRC) to facilitate decompression. It is critical that this process is handled with care and due diligence to ensure that the divers are not exposed to any risk of decompression sickness.

JFD has designed and built multiple advanced HRF systems that are currently in operation. These are designed to allow for the configuration to mate to a recovered SPHL or to a HRC whilst operating anywhere in the world, connecting with a bottom or side-mated SPHL or side-mated HRC, and maximising the chances of a successful rescue.

Of paramount concern

Having a comprehensive rescue and evacuation process in place that covers all eventualities and caters for every stage of rescue is absolutely vital to ensure the safety of divers. Health and safety must always be the primary concern for any operation, regardless of how or where it is carried out. To protect the lives of divers it is paramount that the necessary technical capabilities are in place to safely facilitate an escape and evacuation, from deep sea to the shore. This means providing divers with the ability to return to safety at pressure, employing technical support solutions that are innovative, reliable, fit for purpose, and of the highest quality. Divers carry out vital work in keeping the offshore and oil and gas industries afloat, and there can be no greater priority than ensuring their safety whilst they carry out their work.

Danny Gray is operations director at JFD

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