Smoke exhaust – it’s serious
The 2019 budget rate for a powered system is R225 000 in
South Africa. Please note this pertains to a simple building
as described above.
STANDARD SOPHISTICATED HOTEL BUILDING
Standard sophisticated hotel buildings do not relate to the
“Star Rating” system. They relate to the level of detailing
and complex structure of the building. A simple building
could easily carry a high “Star Rating” but from a fire
perspective be simpler and easier to design.
Parking basement areas
As soon as the hotel has a basement, the building evolves
into a sophisticated building. The basement requires a smoke
ventilation system and a CO extraction system. The different
lifestyles of the occupants need careful attention and no longer
require a simple CO monitoring system.
Mean average weighting of CO levels become important.
Normally a smoke clearance system is required, a basement
automatically requires sprinkler protection, and if not for the
protection of the structure, sprinklers are definitely required
for the protection of the smoke ventilation equipment. The
controls are complex, and evacuation of people is a primary
concern that affects the control of the system.
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RACA Journal I June 2019
Second, multi-level basements in the building move the
building in to the complex space. The evacuation staircase
adds additional complexity to the staircase pressurisation
system. Air is required to be ducted to the lowest level of the
basement. The stair cannot be pressurised from high level
and pass the evacuation level and then extend below this
level. It is not possible to get the air past the evacuation level
without a ducted system.
Occupied floors and areas
The occupied level of the building requires similar attention
to the standard simple building. There may be a scattering
of double volume areas and this becomes an automatic
concern, specifically from a financial perspective. A double
volume area from a budgeting perspective equates to
approximately three single level smoke zones (R675 000).
Attention to the travel distances, less than 60m for smoke,
need to be adhered to from a compartmentalisation
perspective. Attention to the lift shafts remains paramount
to the success of the smoke ventilation system.
COMPLEX BUILDING
Parking basement areas
Complex buildings consist of multi-level basements. The
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