703.7 Building house traps.

Building house traps shall be installed on all building drains in accordance with Section 1002.6.

703.7.1 Fresh air inlets.

Every sanitary or combined building drain shall be provided with a fresh air inlet pipe connected to the building drain immediately upstream from and within 4 feet (1219 mm) of the building trap. Such connection shall be made in the same manner as prescribed in Section 905 for vent connections to horizontal drains, and the fresh air inlet pipe shall be extended to the outer air and shall be terminated in an open end at least 6 inches (152 mm) above grade. The open end shall be protected by a perforated metal plate permanently fixed in the mouth of the inlet and having an open ventilating area at least equal to the area of the pipe, or by a return bend with its unprotected open end at least 6 inches (152 mm) above grade, located inside the street line. The size of the fresh air inlet pipe shall be at least one-half the diameter of the building drain at the point of connection, but not less than 3 inches (76 mm).  

(Am. L.L. 2023/077, 6/11/2023, eff. 6/11/2023)

Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 2023/077.

703.7.2 Fresh air inlets located in flood hazard areas.

Fresh air inlets located in flood hazard areas shall be located above the design flood elevation in accordance with Section G304 of Appendix G of the New York City Building Code.

Section PC 704: Drainage Piping Installation

704.1 Slope of horizontal drainage piping.

Horizontal drainage piping shall be installed in uniform alignment at uniform slopes. The slope of a horizontal drainage pipe shall be not less than that indicated in Table 704.1.

Table 704.1
Slope of Horizontal Drainage Pipe

 

Size (inches)	Minimum Slope (inch per foot)
2 1/2 or less	1/4
3 to 6	1/8
8 or larger	1/16

 

For SI: 1 inch = 25.4 mm, 1 inch per foot = 83.33 mm/m.

704.2 Change in size.

The size of the drainage piping shall not be reduced in size in the direction of the flow. A 4-inch by 3-inch (102 mm by 76 mm) water closet connection shall not be considered as a reduction in size.