highest point, and not greater than 6m head at the lowest point of the section. Steeply graded pipelines shall be tested in stages in cases where the maximum head, as stated above, would be exceeded if the whole section were tested in one length. 

The pipeline shall be filled with water and a minimum period of 2 hours shall be allowed for absorp- tion, after which water shall be added from a measuring vessel at intervals of 5 minutes and the quality required to maintain the original water level noted. Unless otherwise specified, the length of pipeline shall be accepted if the quantity of water added over a 30 minute period is less than 0.5 liter per linear meter per meter of nominal bore. 

## 5.3.10.6 Air Test for Non-Pressure Pipelines 

Non-pressure pipelines to be air tested shall have air pumped in by suitable means until a pressure of 100 mm head of water is indicated in a U-tube connected to the system. The pipeline shall be accepted if the air pressure remains above 75 mm head of water after a period of 5 minutes without further pumping, following a period for stabilization. Failure to pass the test shall not preclude acceptance of the pipeline if a successful water test, ordered by the Engineer, can subsequently be carried out. 

## 5.3.10.7 Testing of Pressure Pipelines (excluding PVC and Polyethylene pressure pipes) 

Hydrostatic testing of pressure pipelines shall be performed in accordance with the requirements of EN 805 or as specified below: 

a) The entire pipeline shall be pressure tested. 

b) Gauges used for testing pressure pipelines shall either be of the conventional circular type, not less than 200mm diameter, calibrated in meters head water, or shall have a digital indicator capable of reading increments of 0.1m head. Before any gauge is used, the Contractor shall ar- range for it to be checked independently and a dated certificate of its accuracy shall be provid- ed. 

c) Before testing, valves shall be checked and sealed, the sections of pipeline filled with water and the air released. After having been filled, pipelines shall be left under operating pressure for 24 hours, so as to achieve conditions as stable as possible before commencing testing. 

d) The pressure in the pipeline shall then be raised steadily until the specified test pressure is reached in the lowest part of the section, and the pressure shall be maintained at this level by pumping if necessary, for a period of one hour. The pump shall then be disconnected, and no further water shall be permitted to enter the pipeline for a further period of one hour. At the end of this period the original pressure shall be restored by pumping and the loss measured by drawing off water from the pipeline until the pressure as at the end of the test is again reached. 

e) The permissible loss shall not exceed 2 liters per meter nominal bore per kilometer length per meter head (calculated as the average head applied to the section) per 24 hours. 

f) Test pressures shall be 1.5 x working pressure, with a minimum of 6 bars, except where instructed by the Engineer. 

g) All testing apparatus and materials including cap-ends, blank flanges, etc. shall be provided by the Contractor. The Contractor shall provide all labor, plant and materials to carry out the pressure testing. 

h) The Contractor shall be responsible for the supply of water for pressure testing. Water for dis- posal must be channeled to the nearest available watercourse/storm water drainage system as approved by the Engineer. 

i) For the duration of the test air valves shall be isolated, valve gland packings shall be tightened down where applicable, and re-adjusted on completion of the successful test. 

