Technical Booklet L Combustion Appliances and Fuel Storage Systems·Page 60·4.21
Protection of vulnerable flue outlets
Flue outlets in vulnerable positions, such as within reach of ground, balconies, verandas, or windows, must be designed to prevent obstruction of the flow by debris or other matter.
If a flue outlet is in a vulnerable position, such as where it discharges at a point within reach of the ground, a balcony, a veranda or window, it should be designed to prevent the entry of any matter that could obstruct the flow.
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