What is the requirement for an Air Gap installation in relation to the discharge pipe?

The requirement for an air gap installation is meant to prevent backflow contamination, which is a crucial aspect of irrigation system design and health safety. When determining how the receiving pipe relates to the discharge pipe, the specifications aim to ensure there is adequate separation to provide an effective air gap.

Choosing the option where the receiving pipe must be 1 inch wider or two times bigger than the discharge pipe correctly captures the essence of these design requirements. This flexibility allows for adaptability in varying installation scenarios, ensuring that whichever condition is applied, it still maintains a sufficient barrier for preventing contamination. An air gap creates a physical barrier, not just a measurement, reinforcing that it is not solely about matching sizes but ensuring that the gap is functionally effective.

In contrast, other options that suggest either a fixed diameter relationship or simply matching sizes do not provide the necessary safety margin or flexibility that is critical in real-world applications. Thus, selecting the correct answer reflects an understanding of the standards designed to uphold safety in irrigation systems.