Two fixtures set on the same floor level and connecting to a common vertical drain within the required distance may share…

Giải thích

Two fixtures at the same level connecting to a shared vertical drain within the code distance may be served by a common vent, with the connecting drain and vent sized for the combined load. Each fixture still has its own trap; a single trap serving two fixtures is generally prohibited. Common venting saves piping for back-to-back layouts.