The Ontario Building Code | Construction Requirements
8.8.2.1. Construction Requirements
(1) All Class 5 sewage systems shall be equipped with a device that shall produce an audible and visual warning alarm so located to warn that the sewage system is nearing capacity.
(2) The device required in Sentence (1) shall be designed to provide suitable advance warning to the building occupants considering,
(a) the total daily design sanitary sewage flow,
(b) the location of the Class 5 sewage system, and
(c) the response time of the hauled sewage system contractor.
(3) Except as provided in Sentence (4), all holding tanks shall be provided with a vent that,
(a) is not less than 3 in. trade size,
(b) terminates at least,
(i) 300 mm above finished grade with a vent cap, or
(ii) 600 mm above finished grade with a vent cap when the holding tankis located in an area subject to flooding, and
(c) terminates at least 3.5 m away from any air inlet, window, or door.
(4) A vent from a holding tank may connect into the venting ="http://thehandyforce.com/interior/bathroom-renovations/" title ="Toronto Bathroom renovation inspiration">venting system of the building served by the holding tankprovided that,
(a) the vent is not less than 3 in. trade size, and
(b) the installation of the vent shall conform to the requirements in Part 7.