1. Describe oxygen, when to use? What is the difference between oxygen gaseous system and oxygen generator?
(1) Oxygen system install in aircraft can be classified into chemical gas generator type and gaseous system type including continuous flow and diluter demand. Oxygen system supplies oxygen to passenger and crew members in the event of that oxygen content in cabin is insufficient or cabin altitude above the predetermined value, usually 14000 ft. which are likely causing 'ANOXIA" to the person in the aircraft. In addition it its used when aircraft is in emergency such as cabin fire producing toxic smoke to the passenger and crew members. In addition, portable oxygen sets are also provided for therapeutic purpose and for cabin attendants using while moving inside the cabin in low pressure emergency.
(2) For oxygen gaseous system:
Oxygen stored in a cylinder under pressure and is reduced to the low pressure by a regulator valve. Oxygen distributes to the passenger and crew continuously through the masks which drop automatically by the aneroid switch or normal operated by the flight crew when the mask is pulled, the valve will open and give out oxygen to the user.
(3) For chemical oxygen generator:
A compressed block of sodium chlorate with iron powder is used to generate oxygen. Then the oxygen mask is pulled, it will trigger the firing mechanism. As the temperature increases, the sodium chlorate with the iron powder will generate low pressure oxygen which passes through the filter and supply to the user. This system supplies oxygen only once by the chemical reaction.
(4) The difference between the gaseous oxygen and oxygen generator: