What type of oxygen masks are used in the flight deck?

The type of oxygen masks used in the flight deck are known as quick don masks. These masks are specifically designed for emergency situations, allowing pilots to don them quickly and efficiently when cabin pressure is lost or in the event of smoke or fire in the cockpit. The quick don feature is critical because there may be very little time to react in an emergency, and the ability to put on the mask rapidly can be vital for the pilots' safety and the safety of the flight.

Quick don masks generally have a system that allows the wearer to put them on with one hand, enabling them to maintain control of the aircraft with the other hand if necessary. This is particularly important in a high-stress environment where speed and efficiency can make a significant difference in outcomes.

The other types of masks mentioned serve different purposes and might not provide the same urgency or ease of use required in the flight deck context. Standard masks for general use may not have the quick-don capabilities, while portable and disposable masks are often used in different contexts such as passenger use, and do not meet the specific requirements of the flight deck environment.