Plumbing Engineers Handbook – Volume 2

Full Description

The purpose of the sanitary drainage system is to remove effluent discharged from plumbing fixtures and other equipment to an approved point of dis- posal. A sanitary drainage system generally consists of horizontal branches, vertical stacks, a building drain inside the building, and a building sewer from the building wall to the point of disposal.
To economically design a sanitary drainage system, use the smallest pipes according to the code that can rapidly carry away the soiled water from individual fixtures without clogging the pipes, leaving solids in the piping, generating excessive pneumatic pressures at points where the fixture drains connect to the stack (which might cause the reduction of trap water seals and force sewer gases back through inhabitable areas), and creating undue noise.
Since vents and venting systems are described in Chapter 3 of this volume, the following discussion cen- ters only on the design of drain and waste systems.