Technical Booklet K Ventilation·Page 34·2.77
Smoke and fire spread prevention in protected stairways
Where ducts are provided in dwellings with protected stairways, precautions must prevent the ventilation system from allowing smoke or fire to spread into the stairway.
Where ducts, etc. are provided in a dwelling with a protected stairway, precautions should be taken to avoid the possibility of the system allowing smoke or fire to spread into the stairway.
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