How long must the RO machine operate continuously before conducting chlorine testing?

The correct response emphasizes that the reverse osmosis (RO) machine should operate continuously for 15 minutes before conducting chlorine testing. This duration is essential to ensure that the system stabilizes and any residual chlorine has been adequately flushed from the system. By allowing the system to run for this period, it helps achieve a consistent flow and pressure, which can improve the accuracy of the chlorine measurement. Chlorine testing ensures that any incoming chlorine does not affect the quality of the water in the dialysis process, thus ensuring patient safety.