A by-pass line shall be installed around water meters ___________ inches and larger.

In accordance with plumbing codes, the installation of a by-pass line around water meters is typically required for larger meters in order to facilitate maintenance and ensure continuous service. For water meters that are 1-1/2 inches and larger, having a by-pass line allows for the water supply to continue uninterrupted while repairs or maintenance work is performed on the meter itself.

The requirement specifically for 1-1/2 inches and above is based on the increased flow and demand characteristics associated with larger meters. A by-pass line is essential for efficient operation, as it helps to prevent disruptions in water service to the client, particularly in commercial or industrial applications where water service continuity is critical.

The other size options, 2 inches and 3 inches, are progressively larger but do not represent the base requirement set by the code for the installation of by-pass lines. Therefore, only the option indicating 1-1/2 inches establishes the minimum size where this practice is mandated.