What does "Containment" protection imply in a backflow prevention context?

In the context of backflow prevention, "Containment" protection refers specifically to safeguarding the entire water supply system of a facility from contamination that could occur from the plumbing system. It does not offer full protection to each individual plumbing system within the facility. Instead, containment focuses on preventing any contaminated water from flowing back into the main public water supply, thereby protecting the broader water system.

When "Containment" measures are in place, they create a barrier that keeps the water safe for consumption at the supply point; however, they do not necessarily prevent potential contaminants from entering individual plumbing systems within the facility itself. This means that while the facility maintains a safeguard against backflow into the mains, the individual plumbing systems may still be at risk if they are not adequately protected. Therefore, the notion that it offers "no protection to individuals in the facility" could be seen in the context that, while containment protects the water supply at a larger scale, individual systems inside a facility require their own protection measures to ensure safe drinking water at every tap.

The other options imply various levels of protection or certainty that go beyond what containment alone can ensure, particularly with regard to individual plumbing systems or specific types of backflow risks.