Final answer:
An air gap is an alternative method that can be used to avoid backsiphonage. It provides a physical separation between the water supply outlet and potentially contaminated source, ensuring no backflow or backsiphonage can occur.
Step-by-step explanation:
An alternative method that can be used to avoid backsiphonage is air gap. An air gap is a physical separation between the water supply outlet and any potentially contaminated source. It ensures that there is no possibility of backflow or backsiphonage since there is an open air gap between the two.
For example, in plumbing systems, an air gap is often used to prevent contaminated water from flowing back into the clean water supply. The air gap creates a break in the pipe where water can spill out and prevent any backflow.
Gravity feed, cross-connection, and direct connection do not provide the same level of protection against backsiphonage as the air gap method.