If the first disinfection test for a pipe does not meet minimum standards, what is the recommended next step?

• A. Test the water again
• B. Proceed with construction
• C. Ignore and continue
• D. Immediately replace the section

Answer: (A)

When a newly disinfected pipe doesn’t pass the initial test, the immediate next step is to test the water again. This retest confirms whether the failure is real or due to sampling or procedure quirks, and it helps determine if issues like incomplete flushing, inadequate contact time, or uneven disinfection can be corrected before proceeding. Make sure the retest follows proper sampling methods, with the system flushed and the disinfectant residual verified. If the retest still doesn’t meet standards, then take the appropriate corrective actions.