Technical Booklet K Ventilation·Page 36·2.96
Ducts in protected stairways
Where ducts are provided in dwellings with protected stairways, precautions may be necessary to prevent smoke or fire spread into the stairway.
Where ducts, etc. are provided in a dwelling with a protected stairway, precautions may be necessary to avoid the possibility of the system allowing smoke or fire to spread into the stairway.
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