Civil Engineering Reference
In-Depth Information
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A fl oor above 7.5 metres if it is used as a:
valves positioned at ground fl oor level. Every landing in
the building has an outlet valve, sometimes located in
a cupboard. Dry rising mains rely solely on the ability
of fi re service pumps and hoses to pump water up the
building. This limits the use of dry rising mains to a
maximum height of 50 metres.
Foam mains
- in some instances large underground
boiler rooms with fl ammable oil storage are fi tted with
dry mains that facilitate the application of fi re fi ghting
foam from a fi re service pumping appliance. The foam
main allows fi re fi ghters to apply premix foam, which
is aerated and applied at the seat of the fi re, from the
outside of the building.
Wet rising mains
- where a rising main is required
to be used for fi re service at a height above 50 metres, it
is necessary to provide wet risers. Wet risers are similar
to dry risers apart from that they are constantly charged
with a water supply from a source that is able to provide
water at a suffi cient pressure to reach the required
height.
Falling mains
- falling mains are identical to rising
mains apart from the fact that they serve fl oors below
the normal level of access. Falling mains are used for
extensive basement areas.
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Shop, or commercial building
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Public assembly or recreational building
➤
Any storage or other non-residential building
that is not sprinklered
Two or more basements of over 900 m
2
.
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It should be noted that the outlets from the fi re mains
should be located within the protected fi re fi ghting shaft
to enable fi re fi ghters to connect their equipment to the
fi re main in the relative safety of the protected shaft.
A fi re fi ghting lift is required if the building has a fl oor
more than 18 m above, or more than 10 m below, the fi re
service vehicle access level.
Suffi cient fi re mains
Fire mains should be provided in all buildings that
require a fi re fi ghting shaft.
Dry rising mains
- as the name suggests all dry
water mains are fi tted vertically within a building. They
are operated exclusively by the fi re service who when
necessary will 'charge' the dry mains with water via inlet
BUILDINGS IN WHICH FIREFIGHTING SHAFTS SHOULD BE PROVIDED;
SHOWING WHICH STOREYS NEED TO BE SERVED
The upper storey(s) in
Purpose Groups 4, 6 & 7a
buildings with a storey of
900 m
2
or more which is
moe than 7.5 m above fire
service vehicle access level
The upper storeys
in any building
with a storey more
than 18 m above
fire service vehicle
access level
The basement storeys in any building with
2 or more basements each exceeding 900 m
2
Fire service vehicle
access level
Fire service
vehicle access
level
7.5 m
The basement
storeys in any
building with a
basement more
than 10 m below
fire service vehicle
access level
B
A
B & C Firefighting shafts need not include a firefighting lift
A Firefighting shafts should include firefighting lift(s)
Note
: Height excludes any top storey(s) consisting exclusively of plant rooms.
Figure 9.86
Buildings in which fi re fi ghting shafts should be provided
