scope:

Description

Vacuum toilet assemblies and GWDUs consist of a connection to potable water stored on the aircraft, a waste collection receptacle, a means to rinse the waste collection receptacle, a means to protect the potable water supply, and a connection to the vacuum waste system. The potable water system protection shall vent to the cabin pressure. The vacuum toilet assemblies and galley waste disposal units shall be integral only to devices specified by the manufacturer.

This Standard does not cover bidets nor washlets.

Vacuum breakers will be classified as atmospheric type, as described herein.

The atmospheric type vacuum breaker design shall fulfill the functions of:

a) A check valve member

b) An air inlet valve that is closed when the check valve member is open, and normally open when the check valve member is normally closed.

A suitable means of protection for the air inlet of AVB used on vacuum toilet assemblies and GWDUs shall be provided.

AVBs shall be installed on the discharge side of the last control valve in the potable water supply line and shall be designed so as to be protected from physical damage and contamination.

Sizes

The integrally-applied vacuum breaker assemblies' inlet and outlet sizes are determined based on the smallest fitting to which they are designed to be installed. The inlet and outlet pipe sizes shall range from ⅛ inch NPS to ½ inch NPS (3 mm to 15 mm).

Working Pressure

The vacuum breaker shall be designed to operate at the minimum potable water system pressure as specified by the aircraft manufacturer. The vacuum breaker shall be designed to operate up to a maximum working pressure of 50.0 psig (344.7 kPa).

Temperature Range

Devices limited to cold water service shall operate within a range from 33 °F +2.0 °F, -0 °F to 110 °F +0 °F, -2.0 °F (0.6 °C +1.1 °C, -0 °C to 43.3 °C +0 °C, -1.1 °C).

Accessibility

The AVB, rinse valve, or combination thereof shall be accessible, either on or off the aircraft, for adjustment, repair, or replacement.