What is the first step in the treatment of hypoxia when a diver is submerged?

In the context of treating hypoxia in a submerged diver, performing Emergency Procedures (EPs) for the rig is considered the first step because it focuses on immediate actions that can stabilize the situation. Ensuring the safety of the diver and the surrounding environment is paramount. This involves assessing the diver's condition and ensuring they can be safely brought to the surface or to a controlled atmosphere where proper treatment can be initiated.

When a diver is submerged and experiencing hypoxia, immediate response is critical. This typically includes emergency protocols customized for the underwater environment, such as surfacing the diver safely if feasible and ensuring proper buoyancy. These steps are vital as they can prevent further complications and allow for additional medical interventions to be put in place once the diver is in a safer position.

Once the initial emergency procedures are completed, actions such as administering pure oxygen may be warranted, but they come after ensuring the diver is out of immediate danger. Thus, the priority is to first manage the dive environment and the diver's immediate safety before moving on to specific medical treatments or rescues.