Which two types of portable oxygen bottles are onboard United aircraft?

Which two types of portable oxygen bottles are onboard United aircraft?

• A. Portable oxygen bottle and portable pulse oxygen bottle
• B. Emergency oxygen bottle and portable oxygen bottle
• C. Medical oxygen bottle and portable oxygen bottle
• D. Liquid oxygen cylinder and portable oxygen bottle

Answer: (A)

The main idea is that United aircraft use two kinds of portable oxygen bottles for passenger use: a standard portable oxygen bottle that provides continuous flow, and a portable pulse oxygen bottle that uses a demand regulator delivering oxygen only when you inhale. The continuous-flow bottle supplies a steady stream of oxygen whenever it's opened, which is straightforward but uses more oxygen. The pulse-demand bottle is more efficient because it detects breathing and releases a dose of oxygen with each inhalation, conserving the supply for longer flights. Other options refer to systems that aren’t portable passenger bottles (like the aircraft’s fixed emergency oxygen system) or to types not typically carried for regular passenger use (such as medical oxygen or liquid oxygen cylinders). So the two portable types onboard are the standard portable oxygen bottle and the portable pulse oxygen bottle.

The main idea is that United aircraft use two kinds of portable oxygen bottles for passenger use: a standard portable oxygen bottle that provides continuous flow, and a portable pulse oxygen bottle that uses a demand regulator delivering oxygen only when you inhale. The continuous-flow bottle supplies a steady stream of oxygen whenever it's opened, which is straightforward but uses more oxygen. The pulse-demand bottle is more efficient because it detects breathing and releases a dose of oxygen with each inhalation, conserving the supply for longer flights. Other options refer to systems that aren’t portable passenger bottles (like the aircraft’s fixed emergency oxygen system) or to types not typically carried for regular passenger use (such as medical oxygen or liquid oxygen cylinders). So the two portable types onboard are the standard portable oxygen bottle and the portable pulse oxygen bottle.