Home » Method Statements » Drainage System Testing & Commissioning Procedure

Drainage System Testing & Commissioning Procedure

Pre-Commissioning Phase

System Pre-Commissioning Checks


Before commissioning the system the following shall be ensured.

a) The Installation and Leak testing of the pipes are completed.

b) The installations sanitary wares (WC, Wash Basin, etc.) are completed.

c) The sanitary wares are properly operating.

Commissioning Phase

Commissioning Checks for Drainage System

a) Complete installation of Drainage system as per the approved drawings & method statement of installation.

b) Complete leak testing for all the floors & the risers as per method statement for testing, and hand over all leaks testing to consultant & contractor.

Performance Test

a) Check all sanitary wares by discharging individually and by group; it should drain speedily, quietly and completely.

b) Check the Floor drain/trap water seal by dip stick or small diameter transparent tube, a minimum of 25 mm of water seal should be retained in every trap.

c) Repeat a & b test three (3) times with the trap or traps being recharged before each test.

Tests for self-siphonage and induced siphonage in branch discharge pipes.

a) To test for the effect of self-siphonage the sanitary wares (wash basin, sink, and bath tub) should be filled to overflowing level and discharged by removing the plug; WC pans should be flushed.

b) Measure the seal remaining in the trap when the discharge has finished.

c) Ranges of Sanitary wares, connected to a common discharge pipe, should also be tested for induced siphonage in a similar way.

d) Refer to the agreed number of sanitary wares that should be discharged together.

e) Measure the seal remaining in all the traps at the end of the discharge.

Note: The worst conditions usually occur when the sanitary wares at the upstream end of the discharge pipe are discharged.

Test for induced siphonage and back pressure in discharge stacks

a) Discharge simultaneously a selection of Sanitary wares (WC, wash Basin) connected to the stack.

b) Check & monitor the trap and seal losses due to positive or negative pressures in the stack.


Enter your email address & Click Join:

Check Also

Ring Main Unit Testing and Commissioning Method Statement

Required tools for ring main unit testing and commissioning procedure: Primary Injection kit Contact Resistance …