Testing and Commissioning Method Statement For Water Supply System Chlorination is give below in the order of sequence for the process.
- Pre-Commissioning Phase: Pre-Commissioning Checks
The main objective here is to prepare and check the installation of piping and domestic water tank prior to Chlorination of the Water Supply System.
- The following checks will be made and recorded on the test sheets.
• Check that the booster pump is installed and operational.
• Check that all filtration, softener, water heaters & calorifiers systems are bypassed prior to chlorine application.
• Check that the isolation valve is installed for inlet and outlet.
• Check if the strainer is installed.
• Verify that the piping system tests are complete.
• Verify that the tank installation is approved and the required test is completed.
Commissioning Phase: Commissioning Procedure for Chlorination
- Isolate the system to be treated from public use.
- Attach suitable hazard warning notice at all main entrances like toilet areas, tank room and the like.
- Fill the water tank with fresh water and run the booster pump to distribute the water to the whole system
prior to flushing.
- Drain the water tank and the distribution system to empty and physically clean, to remove all deposits of rust, slime, sediments, scale and other fouling, as far as is practicably possible.
- Fill the water tanks again with fresh water and then close off the make-up supply line.
- Chlorinate the water in the water tank by adding the approved chemical or Tablets, to give a measured free chlorine level of minimum 50 ppm in the water. This can be measured using testing chlorine kit provided. Yellow color indicates 50 ppm and above, otherwise additional chemical tablet is required.
- After an hour, Charge the system with the chlorinated water from the water tanks. Note: All filtration, softener, water heater and calorifier systems should be bypassed.
- After Chlorinating the water tank and pipeline, each draw off fitting should be successively opened working progressively away from the water tank & pipeline. Each tap and draw-off fittings should be closed when the water discharging begins to smell of chlorine. Note: The water tanks & pipelines must not be allowed to become empty during this operation, if necessary it must be refilled and chlorinated as above. The water tanks and pipelines should remain charged for 24 hours.
- After 24 hours, Open a selection of outlets, including those furthest or highest from the water tank, measure the free chlorine level. If the concentration of the free residual chlorine is less than 30 ppm (Using Testing Kit, pink color should be produced) the disinfecting must be repeated. Otherwise, drain 20% of the water in the water tank.
- After Draining Dose chlorine neutralizing solution @ 1.55 ppm per 1 ppm of free chlorine.
- After the addition of neutralizing solution, charge fresh water tank with fresh water equivalent to the 20%
that was previously drained.
- Wait for 3-4 hours before charging the system. In charging the system, all outlet/taps to be open to release
the water until the water coming out of the taps are clear and not smelling chlorine.
- Sample for microbiological test has to be collected from designated location.
- The sample will be tested by approved laboratory.
- Final Certification will be provided upon satisfactory completion of the above.