Which of the following methods involves flushing traps after mixing the chlorine solution?

The re-chlorination procedure is a method that specifically focuses on treating water by adding chlorine after initial disinfection processes. This technique often involves flushing the traps, which are areas of plumbing that can retain contaminants, with a chlorine solution. The purpose of this flushing is to ensure that any residual or reintroduced contaminants are effectively eliminated, thereby maintaining the safety and quality of the water supply.

In contrast, filtration involves physically removing particles from water but does not specifically concern the action of flushing with chlorine. Chlorination refers primarily to the initial addition of chlorine for disinfection purposes. Disinfection encompasses various methods to kill or deactivate harmful microorganisms but does not focus solely on the flushing aspect described in the question. The re-chlorination procedure specifically aligns with the process of mixing and using a chlorine solution for the purpose of maintaining water quality and safety after it has been previously treated.