(1)
Where a storm drainage system is connected to a combined building sewer or a public combined sewer, a trap shall be installed between any opening in the system and the drain or sewer, except that no trap is required if the opening is the upper end of a leader that terminates
(a)
at a roof that is used only for weather protection,
(b)
not less than 1 m above or not less than 3.5 m in any other direction from any air inlet, openable window or door, and
(c)
not less than 1.8 m from a property line. (See Note A-7.4.5.2.(1))
(2)
A floor drain that drains to a storm drainage system shall be protected by a trap that
(a)
is located between the floor drain and a leader, storm building drain or storm building sewer,
(b)
may serve all floor drains located in the same room, and
(c)
need not be protected by a vent pipe.