Diving with EANx (enriched air nitrox) involves using a breathing gas with an oxygen volume of at least 22 percent, commonly utilized in both open circuit SCUBA and rebreather equipment. WorkCover Queensland emphasizes the importance of managing the risks associated with elevated partial pressures of oxygen (PPO2) while benefiting from reduced exposure to elevated partial pressures of nitrogen.

Rebreathers, which employ a breathing circuit, maintain air quality by using chemical absorption to remove carbon dioxide while adding oxygen and diluent. These systems, equipped with in-line sensors and computers, offer benefits such as quiet operation, customizable breathing gas mixtures, and efficient gas usage. However, potential risks include system flooding and failures in the breathing circuit components, leading to toxic or hypoxic breathing gas.

When using EANx with SCUBA, WorkCover Queensland highlights the need for additional skills, equipment, procedures, training, and supervision. The responsibilities of persons conducting a business or undertaking (PCBU) include ensuring the presence of an EANx dive supervisor, limiting EANx diving to certificated individuals, and adhering to specific PPO2 exposure limits and maximum dive depths. Divers should conduct gas analysis before use and be informed about dive plans, emergency procedures, and equipment checks.

For EANx rebreather diving, WorkCover Queensland stresses the importance of an EANx rebreather dive supervisor or an EANx dive supervisor ensuring appropriate checks on the rebreather unit. Certificated EANx rebreather divers should adhere to PPO2 exposure limits and maximum dive depths, conduct gas analysis, and avoid using rebreathers for non-certificated diving experiences. Divers should be advised on dive plans, objectives, safety requirements, and emergency procedures, including manufacturer-recommended pre-dive checks and guidance on carbon dioxide scrubbers.