Section 49(6) in Assam Notified Urban Areas (Other than Guwahati) Building Rules, 2014
(6)Every septic tank shall be provided with ventilating pipe of at least 50 mm diameter. The top of the pipe shall be provided with a suitable cage of mosquito proof wire mesh. The ventilation pipe shall extend to a height, which would cause no shell nuisance to any building in the area. Generally, the ventilating pipe may extend to a height of about 2m when the septic tank is at least 15m away from the nearest building and to a height of 2m above the top of the building when it is located closer than 15m.
