What is verified during the preflight check of the O2 tool?

During the preflight check of the O2 tool, verifying the very presence of the tool is crucial. This step ensures that the oxygen tool is onboard and readily accessible to crew members in case of an emergency where supplemental oxygen is required. Ensuring the presence of the tool helps to maintain safety protocols and guarantees that necessary equipment is available for passenger or crew member use.

While verifying the expiration date, connection integrity, and functionality are also important aspects of maintaining the O2 tool, they represent different levels of checks, including checks for operational status and safety compliance. The primary focus during the preflight check is to confirm that essential safety equipment, like the O2 tool, is physically available, which is the foundation for being prepared for emergencies.