This Specification refers to various FAA regulations.

The door used for entrance and exit of the passengers and crew to and from the aircraft. Includes items such as structure, latching mechanisms, handles, insulation, lining, controls, integral steps, ramps, and handrails, etc.

The doors inside the fuselage installed in fixed partitions. Includes items such as structure, latching mechanisms, handles, lining, etc.

Stairs whose primary structure is a door shall be covered under the appropriate topic. Includes items such as structure, actuating mechanisms and controls, handrails, etc.

Electrical/electronic panels and multipurpose parts are complete coverage of all general purpose electrical and electronic parts.

Air supply system is that portion of the system common to more than one subsystem which is used for pressurizing supply tanks to insure fluid flow.

Potable system is that portion of the system which is used to store and deliver fresh drinking water.

Water/waste subsystem includes wash basins, toilet assemblies, tanks, valves, etc., if applicable.

Distribution subsystem is that portion used to distribute below atmospheric pressure air to using systems.

Distribution system includes items such as ducts, valves, actuators, heat exchangers, controls, etc. Does not include the supply valves to the using systems.

Distribution system refers to that portion of the system which is used to distribute high or low pressure air to using systems.