For hospitals suspecting Legionella contamination following a water main break, how should flushing be ideally conducted?

Flushing a plumbing system after a water main break is a critical procedure, especially in a hospital setting where the risk of Legionella contamination can have severe health implications. Flushing should be conducted upstream of all outlets prior to contamination spreading, as this will help remove stagnant water that may harbor Legionella bacteria.

When a water main break occurs, there is a potential for contaminated water to enter the building's plumbing system. By flushing upstream of outlets, the goal is to clear out any contaminated water before it reaches faucets or other delivery points where patients could be exposed. This proactive approach minimizes the risk of spreading contamination and ensures that the clean water supply is restored quickly.

In contrast, starting the flushing at the water main and working down could risk the reintroduction of contaminants to already flushed areas, as contaminants may remain in downstream pipes. Flushing only high-risk patient areas does not address the overall risk of contamination throughout the system, and flushing at faucets may not adequately eliminate the presence of Legionella if upstream contamination exists. Thus, flushing upstream is the most effective strategy to mitigate the risk of Legionella after a water main break.