1.0 PURPOSE:
2.0 SCOPE:
This procedure applies for chemical sanitization of potable water storage and distribution system at (Company name).
3.0 DEFINITIONS:
4.0 RESPONSIBILITY:
4.1 Engineering personnel is responsible for chemical sanitization of potable water storage and distribution system.
4.2 Engineering head is responsible to ensure compliance.
5.0 PROCEDURE:
5.1 Precautions:
5.1.1 Ensure that all the user points are closed and tag all user points with the “Chemical sanitization under process”.
5.1.2 Remove the pH sensor.
5.1.3 Use safety hand gloves, safety goggles, safety shoes etc., while handling the sodium hypochlorite.
5.2 Sanitization procedure:
5.2.1 Start RO and collect 2000 liters of water in potable water tank.
5.2.2 Follow the safety procedure while handling the sodium hypochlorite by wearing apron, hand gloves, safety shoes, face mask & goggles.
5.2.3 Prepare sodium hypochlorite solution by adding 80 liters of sodium hypochlorite solution into 2000 liters of potable water in the potable water tank.
5.2.4 Start the potable water distribution pump.
5.2.5 Circulate the 4% sodium hypochlorite solution for 60 minutes through the loop and tank.
5.2.6 After 60 minutes, stop the potable water distribution pump.
5.2.7 Drain the solution completely from the potable water tank and user points of the loop.
5.2.8 Close all the valves, which were opened earlier to drain the solution.
5.3 Final Water Rinse:
5.3.1 Start RO and collect potable water in the potable water tank till high level.
5.3.2 Start the potable water distribution pump.
5.3.3 Drain the water completely from the user points.
5.3.4 Repeat the above cycle from 5.3.1 to 5.3.3 for one more time with potable water.
5.3.5 Drain and sample till the free chlorine, pH and conductivity of potable water are within tolerances.
5.3.6 Inform QC for collecting water samples.
5.3.7 Record the chemical sanitization report as per Annexure-I.
5.3.8 Start using water after the approval from the QC department.
5.4 Frequency:
5.4.1 Chemical sanitization shall be carried out when any modification or expansion work has been done in potable water system (or) when microbial growth is increased (or) quarterly ±7 days, whichever is earlier.
6.0 ABBREVIATIONS:
SOP – Standard Operating Procedure
RO – Reverse osmosis
QC – Quality control
7.0 REFERENCE:
Nil.
8.0 LIST OF ANNEXURES:
Annexure-I: Chemical sanitization record of potable water system.
