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| Appendix I | Standard Disinfection Procedure For Domestic Water System |
| 1. | Supervision and Testing: Perform entire disinfection procedure under the supervision of Environment, Health and Safety (EH&S). Provide 5 days notice to schedule procedure. |
| 2. | Contractor's Responsibility: Furnish labor, equipment, materials and transportation to disinfect domestic hot and cold water systems and fire lines directly connected thereto, in conformity with procedures and standards described herein. |
| 3. | Disinfecting Agent: An aqueous solution of sodium hypochlorite (minimum 5.25% available chlorine). The use of powdered hypochlorite and chlorine gas are prohibited unless specifically approved by Environment, Health and Safety (EH&S). |
| 4. | Preliminary preparations: |
| a. | Service Cock: Provide within 3' of the entrance of the supply main to the building, a 3/4" service cock, or valve, for the purpose of introducing the disinfecting agent into the lines. |
| b. | Flushing: After final pressure tests and before draining for disinfection, open each fixture or outlet until the water flow is clear. |
| 5. | Disinfection Procedure: |
| a. | Drain entire domestic water system including fire line. |
| b. | Post suitable warning signs at each outlet: Warning - Do Not Use - Water System Being Chlorinated. |
| c. | Inject disinfectant solution into the system through the service cock by means of a pump, or other pressure device, at a slow continuous rate, simultaneous with a reduced flow from the water main, until the orthotolidin test for residual chlorine at each outlet shows a concentration of at least 50 ppm, but note more than 100 ppm. |
| d. | Close all outlets and valves, including the service valve at the main and the injection cock. Retain the chlorinated water in the system for 24 hours. |
| e. | After the 24 hour holding period, the residual chlorine concentration shall be not less than 50 ppm as shown by the orthotolidin test. |
| f. | Drain and flush entire domestic water system until orthotolidin tests show background residual chlorine concentration at any outlet. |
| g. | Environment, Health and Safety (EH&S) will determine whether samples of water must be collected and analyzed for the determination of bacteriological quality. |
| 6. | Standards Necessary for Approval: |
| a. | The water system shall have been uniformly chlorinated under the supervision of Environment, Health and Safety (EH&S) as outlined in note No. 5 above. |
| b. | The results of water sample analysis shall be negative for the Coliform organisms. |
| c. | If the test for the bacteriological quality of the water in the system does not meet the standards, repeat the disinfection procedure until the specified standards are met. |
| 7. | Final Approval: Environment, Health and Safety (EH&S) will give written approval to the University for acceptance and use of the water system after the above procedures have been successfully completed and the standards met. |
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