from contamination and not flammable . Consider fire resistant materials for any wall mounting or notice boards such as concrete board .
As electricity can be an ignition source , review the proximity of electric switches , sockets and consider the lighting near the gas blending area as there are low voltage sealed lighting options available .
■ Equipment set-up Review the filling and blending system as a whole ; if a system has had additions over time are there any potential risks ? If necessary , seek professional advice if you lack the expertise in the branch .
On a blending system where a booster pump is used , ensure the position of the O2 pump in relation to the throttle is in line with manufacturers recommendations . Often there is a recommended minimum distance between the two , but having them a few metres apart could minimise risk in the event of a fire due to the operator being further away from the pump .
While it is rare for hoses to split , if they do , friction heat caused by the escaping gas can be a source of ignition . Steel braided hoses offer a more robust external structure .
Think carefully about the facility layout taking zoning into consideration to segregate the operator from the equipment and any further hazards in the event of an incident to reduce risk of injury .
■ Opening oxygen valves If a system is pressurised quickly , the adiabatic heat generated can be substantial and if there is contamination present an ignition can occur . Pressurise the system slowly , it is very important to open a valve slightly and then wait , allowing the pressure in the first stage and hoses to build slowly . Allowing time to reach full pressurisation will greatly reduce the risk of a fire , even if there is a degree of contamination present .
■ Handling and storage Oxygen cylinders should be handled with care to prevent damage or leakage . They should be stored in well-ventilated areas away from heat sources , flammable materials , and direct sunlight . Additionally , cylinders should be secured to prevent tipping or falling .
■ Training and education Divers and personnel involved in handling oxygen-rich gases must be fully trained on oxygen safety protocols , including the identification of potential hazards , proper handling techniques , and emergency procedures .
Before operating a mixed gas blending panel , divers must undergo comprehensive training and certification to ensure they understand the intricacies of gas blending , including gas laws , blending techniques , and safety protocols .
It ’ s advisable to hold refreshers for anyone who is NOT blending gas on a regular basis and also if any changes are made to systems or protocols . Having clearly displayed procedures for use of equipment displayed in view of the blending area is recommended . The use of checklists is especially useful in this respect particularly for those using the facility infrequently .
■ Notification Often club houses and filling facilities can be in isolated environments . In the event of a fire if a single person is injured while filling alone , they may not be able to get out of the building or raise the alarm . Conducting a risk assessment of the filling processes and environment will help identify mitigating procedures , for example notifications when filling is taking place and safely completed or having two people on site , one filling and one outside the building , could be considered .
Emergency Procedures
Despite diligent prevention efforts , oxygen fires may still occur . In such instances , a prompt and effective response is essential to ensure the safety of individuals involved and minimise damage . It ’ s worth reviewing your current risk assessments regarding emergency procedures including the ones listed below :
■ Terminate oxygen flow Immediately shut off the oxygen supply to the affected equipment to prevent the fire from intensifying . The isolation switch should be located away from the oxygen and near the emergency exit , whenever possible .
■ Evacuation Access and Egress in an emergency is essential . Keep exits open when filling for easy evacuation and ensure that exit route ( as well as ensuring ventilation ) is clear and free of dive kit / trip hazards .
■ Fire extinguishers Have appropriate fire extinguishing agents , such as water , CO2 , or dry chemical extinguishers , to suppress the fire . It ’ s crucial to use extinguishing agents compatible with oxygenenriched environments to avoid exacerbating the situation but only action use if safe to do so .
■ Summon emergency services Contact emergency services and provide them with pertinent information , including the location , nature of the incident , and any potential hazards present .
The remodelled compressor and cylinder bank area
Summary
Oxygen fire safety is a critical consideration to anyone blending mixed gas or with access to facilities storing or blending mixed gas . By reviewing your own facilities and processes and educating your fellow divers and clubs , you can develop a deeper understanding of the risks associated with your own activities and develop more robust prevention measures and emergency response protocols to ensure a safe and secure operating environment . Through vigilance , training and adherence to best practices , we can all contribute to minimising the risks . �
19