Final answer:
A plumbing DWV system vent should be at least 10 feet away horizontally from any door or window, or at least 3 feet above the top of the opening to prevent sewer gas ingress and to ensure proper venting.
Step-by-step explanation:
The question relates to the requirements for the proper placement of a Drain-Waste-Vent (DWV) system vent termination in relation to doors and windows. A plumbing DWV system vent should be at least 10 feet away horizontally from any door or window, or at least 3 feet above the top of the opening to prevent sewer gas ingress and to ensure proper venting.
According to building codes, a plumbing DWV vent termination should be located at least 10 feet horizontally away from such a door or window, unless it is at least 3 feet above the top of the opening. This is to prevent sewer gases from entering through the windows or doors and ensures that the vent works properly, providing air to the DWV system to prevent trap siphonage and back-pressure.