1008.1 General.

Building traps shall not be installed except where required by the Authority Having Jurisdiction. Each building trap where installed

← shall be provided with a cleanout and with a relieving vent or fresh-air intake on the inlet side of the trap. [ ] Such trap shall have a fresh air inlet of not less than 4 inch (101.6 mm) diameter pipe. The inlet shall be covered by an approved perforated plate not less than 16 square inches (10,323

mm [2] ). Perforations shall be not more than 3/8 inch (9.6 mm) diameter and provide an aggregate open area of not less than one-half the cross-sectional area of the sewer trap. The air inlet shall be connected to the building side of the trap and shall lead to the open air, terminating at a point not less than 10 feet (3.05 m) from any window or door.