Transcript Ventilation using shafts - Colt Blog
Slide 1
Colt International Ltd
Smoke and environmental ventilation of multi-storey buildings using shafts
Colt Technical Seminar
“People feel better in Colt conditions” | www.coltinfo.co.uk
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 2
A brief history of Colt
•
A private company founded in 1931
•
I J O’Hea OBE (1897 - 1984)
•
2014 Group turnover £146 million
•
Manufactures in the UK, Holland, Germany and China
I J O’Hea
Colt Founder
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 3
Current UK Business Markets
•
Smoke Control
•
Solar Shading
•
Natural Ventilation
•
Louvre
•
Environmental Comfort Control
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 4
Ventilation using shafts – covering:
1.
Ventilation of Fire Fighting Stairs:
• Natural Ventilation to BS 5588 Part 5 and BS 9999
• Natural Shafts to BS 5588 Part 5 and BS 9999
• BRE Shafts to BS 5588 Part 5 and BS 9999
• Mechanical Shafts
2.
Ventilation of Common Corridors in Residential Developments:
• Natural Ventilation to ADB 2006 and BS 9991
• Natural Shafts to ADB 2006 and BS 9991
• Mechanical Ventilation to ADB 2006
3.
Extended Travel Distances in Common Corridors Using Mechanical Shafts
4.
Day to day ventilation and cooling
5.
Pressurisation
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 5
Ventilation using shafts - general
Description:
•
A common shaft passing through multiple levels allowing natural or mechanical ventilation to
the fire floor via the use of dampers or automatic opening devices on each level.
Used for:
•
•
Ventilating fire fighting lobbies to assist fire fighting operations from a fire fighting shaft
and/or
Ventilating common corridors in high rise residential developments.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 6
Ventilation using shafts
1.
Ventilation of fire fighting stairs
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 7
Ventilation using shafts
1.
Ventilation of fire fighting stairs
Fire Fighting:
In fire fighting shafts the fire and rescue services need clear access to every level.
Usual fire fighting protocol is to take the lift to a floor below the fire floor, connect to the dry riser
and then ascend to the fire floor by stair.
The primary objectives of the ventilation system are, therefore:
•
•
to prevent smoke spread into the staircase
to improve conditions in the fire fighting lobby
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 8
Ventilation using shafts
1.
Ventilation of fire fighting stairs
BS 5588 Part 5 and BS 9999 provide prescriptive ventilation recommendations
Stairwell ventilation
•
•
A 1.5m2 openable vent
at the head of the stairwell; or
Lobby ventilation
•
A 1m2 vent (OV) in the fire fighting lobby; or
•
A 3m2 shaft with 1.5m2 dampers on each level
with openings at the top and bottom of the shaft;
or
•
The BRE Method, which is as above, but omits the
opening at the bottom of the shaft.
A 1m2 openable window at each storey
(OV)
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 9
Ventilation using shafts
1.
Ventilation of fire fighting stairs – BRE shaft
•
A 3m2 shaft is connected to the lobbies by
1.5m2 dampers at high level. Only the damper
on the fire floor opens
•
Air inlet is provided via the stairs from the final
exit door and a 1m2 ventilator at the head of
the stairs
•
No air inlet is required at the base of the shaft
– replacement air is drawn from the staircase,
preventing smoke flow into the stair.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 10
Ventilation using shafts
1.
Ventilation of fire fighting stairs – BRE shaft
Visibility in onerous
wind conditions
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 11
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The next obvious step
•
Offers a further reduction in the occupied space taken up by the
system
•
If effective could be used for both fire fighting and means of escape
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 12
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The major challenge is to avoid excessive depressurisation of the lobby to prevent smoke
being drawn in and problems opening doors
This can be avoided by:
Fire Fighting Lobby
negative
•
•
•
•
•
Low level inlet
An inlet shaft
Doors to be open
Grilles in doors
Variable speed fans
Staircase
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 13
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
We developed a standard system that is at least as good as
the BRE smoke shaft and better in adverse wind conditions
•
The system comprises:
-
a small vertical shaft 0.6m2 instead of 3.0m2
a variable speed extract fan set (run and standby)
a pressure sensor in each lobby
a small motorised damper to each lobby
a 1m2 stairwell ventilator
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 14
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 15
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The design has been proven by CFD analysis
•
By replicating the BRE shaft CFD analysis after discussion with BRE
•
By optimising the air flow rate and shaft and damper dimensions to match the BRE shaft
By modelling closed door conditions to ensure that the system:
•
Does not draw excess smoke into the lobby with doors closed (smoke seal doors between lobby
and accommodation are needed for this)
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 16
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
Visibility - doors open
Mechanical shaft
BRE shaft
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 17
Ventilation using shafts
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 18
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
In multi-storey residential buildings, the main escape route is via common corridors and/or
lobbies to protected stairs.
Smoke will spread to the corridor from a fire in an apartment as the occupants make their
escape.
The 2006 version of ADB requires common corridors or lobbies which open onto a stair to be
ventilated. Fire fighting stairs in residential buildings do not require a separate ventilated fire
fighting lobby.
The ventilation system allows the smoke in the corridor to be cleared and ensures that smoke is
prevented from entering the staircase, which could make make escape difficult for occupants of
higher storeys should the whole building need to be evacuated.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 19
Ventilation using shafts
Small single stair apartment buildings
•
Top floor level no more than 11m above ground level
•
No more than 3 storeys above ground level
•
Stair does not connect to covered car park
ADB Requires:
• Openable vent (OV) to each landing level of stair or single OV at head of stair with activation
from bottom of stair.
Also:
• If lobby is ventilated, travel distance from apartment to stair can be increased from 4.5 to
7.5m.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 20
Ventilation using shafts
All other apartment buildings
ADB Requires:
• All corridors/lobbies adjoining stairs to be ventilated
by either natural or mechanical means.
•
The staircase requires a vent with a free area of 1.0m2 from the top storey to outside.
Activation:
• In a single stair building, the vents should be automatic via smoke detectors in the common
access space.
•
In a multi-stair building, the ventilation can be manual, BUT the vent at the top of the stair
must be interlinked to open at the same time.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 21
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Common Corridors can be ventilated, either:
•
Naturally, located on an outside wall with a minimum free area of 1.5m2
•
Naturally, discharged into a vertical smoke shaft, closed at the base
•
Mechanically, using extract and natural inlet or supply fans
•
Mechanically, using pressure differentials, in accordance with BS EN 12101-6: 2005
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 22
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural ventilation
SHAFT
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 23
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Minimum free area under the 2000 edition of ADB
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 24
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Definition of Minimum Free Area, either:
The aerodynamic free area of the ventilator as defined in EN
12101 Part 2: 2003 – Specification for natural smoke and heat
exhaust ventilators.
Or:
"the total unobstructed cross sectional area, measured in the
plane where the area is at a minimum and at right angles to the
direction of air flow"
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 25
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Minimum free area under the 2006 edition of ADB
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 26
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
If a shaft system is used, the following criteria should be met:
The Shaft should:
•
•
•
•
Be closed at the base
Have a minimum cross-sectional area of 1.5m2 with a minimum dimension of 0.85m in either
direction.
Extend at least 0.5m above the highest structure within 2m
Extend 2.5m above the ceiling of the highest level served by the shaft.
The vent into the shaft, the vent at the top of the shaft and any safety grilles in the shaft should all
have a minimum free area of 1.0m2.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 27
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Construction:
The shaft should be constructed from non-combustible material and the vents should be
equivalent to a E30Sa fire door.
The shaft should be vertical with no more than 4m at an inclined angle (max 30o)
Operation:
On detection of smoke in the corridor, the vent on the fire floor, at the top of the shaft and the
top of the stair should all open simultaneously – vents on all other levels should remain closed.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 28
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Exhaust opening
Ventilation damper
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 29
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Typical Roof Installation
Natural Ventilation
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 30
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Internal Damper to shaft, concealed by decorative grille :
•
Equivalent to E30S Fire
rated construction
•
Motor open/closed
•
Natural, minimum free
area 1.0m2
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 31
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Colt Doorman Actuator with fire door to shaft:
•
Equivalent to E30S Fire rated
construction
•
Require a safety grille across shaft at
each level
•
Units on other levels must lock closed
to prevent smoke transfer
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 32
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Approved Document B permits the use of mechanical ventilation for smoke control of
common escape routes but gives no design guidance on how to design such a system.
However based on the experience gained in developing the Colt Shaft for fire fighting
applications, several options are available to reduce the natural shaft from 1.5m2 to 0.6m2
using a mechanical system.
As with the fire fighting system, the main objective is to keep smoke from entering the
staircase.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 33
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – mechanical shafts
Internal Damper to shaft, concealed by decorative grille or flap vent:
•
Equivalent to E30S Fire rated
construction
•
Motor open/closed
•
Mechanical - Typically 0.8m2
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 34
Ventilation using shafts
3.
Means of escape systems – extended travel
An extended lobby can be used to reduce travel, but the lobby “..must not provide direct
access to any storage room, flat or other place containing a potential fire hazard.”
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 35
Ventilation using shafts
3.
Means of escape systems – extended travel
ADB 2006 states: “There may be some instances where some increase on these maximum
figures [travel distances] will be reasonable.” In most circumstances mechanical systems
can be designed to enhance safety.
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 36
Ventilation using shafts
3.
Means of escape systems – extended travel
Options:
•
Natural Exhaust/Mechanical Inlet
•
Mechanical Extract/Natural Inlet
•
Mechanical Extract/Mechanical Inlet
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 37
Ventilation using shafts
3.
Means of escape systems – extended travel
Natural Exhaust/Mechanical Inlet
Has been used by various fire engineers with varying degrees of success.
Positively pressurises the corridor, therefore can risk pushing smoke into other apartments and
staircase.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 38
Ventilation using shafts
3.
Means of escape systems – extended travel
Natural Exhaust/Mechanical Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 39
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
Slightly depressurises the corridor, therefore inlet shaft and dampers need to be
sized carefully to avoid creating a pressure greater than 50 Pa.
Typically, inlet shaft will need to be in order of 1.5m2.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 40
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 41
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
•
On one typical project the Travel Distance was successfully extended from 7.5m to
18m in one direction
•
System modelled in both escape and fire-fighting mode and compared with a
compliant corridor with a natural AOV system.
•
System out-performs natural AOV for both evacuation and for fire-fighting
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 42
Ventilation using shafts
3.
Means of escape systems – extended travel
Modelled to compare with compliant 7.5m corridor with AOV in still wind conditions with
growing fire in apartment.
Smoke spills into corridor during evacuation and then again 10 minutes later when fire
brigade arrive, fire has grown to around 5000 kW
Compliant Corridor
Extended Corridor
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 43
Ventilation using shafts
3.
Means of escape systems – extended travel
Compliant AOV
Extended Mechanical System
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 44
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
Reduces size of inlet shaft to 0.6m2 typically.
Extract to be designed as Colt Shaft without pressure sensing, inlet fan to match
extract rate.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 45
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 46
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
Reversible
•
Particularly useful with a central stair to two extended corridors.
•
Fans need to be truly reversible (standard fans run at approx 60% in reverse), or
additional inlet may be necessary.
•
Detection needs to identify smoke location.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 47
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet Reversible
7.5m+
7.5m
7.5m
7.5m+
A further benefit of this system is that fire fighters can override the system so that both fan
systems can be set to extract, allowing an enhanced clearance system.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 48
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet Reversible
Smoke can be controlled depending
on the fire location
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 49
Ventilation using shafts
4.
What can we do to avoid corridors overheating?
What can we do to avoid corridors overheating?
Supply
Extract
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 50
Ventilation using shafts
4.
Day to day ventilation
Cooling?
A ventilation system based on
supplying outside air alone is able
to achieve temperatures in the
corridor typically 2-5oC above the
outside ambient.
Adiabatic cooling can reduce
supply temperatures well below
outside ambient, providing active
cooling in the corridors.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 51
Ventilation using shafts
5.
Pressurisation
•
Supply air
•
Distribution Ductwork
•
Pressure Relief
•
Air Release
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 52
Ventilation using shafts
5.
Pressurisation
•
Optimum protection
•
Expensive
•
Complex design
•
Puts more demands on quality of building construction
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 53
Ventilation using shafts
Conclusions
The work of the BRE resulted in alternative methods of ventilation being considered, which have
been incorporated into Approved Document B.
This has paved the way for many new developments in the use of mechanical ventilation shafts in
numerous applications.
•
If space is tight and a shaft system is needed, a mechanical shaft is the solution
•
If dead end corridor lengths exceed prescriptive limits, a mechanical shaft system with
improved performance is the solution
•
Further guidance can be found in a free Smoke Control Association guide, downloadable
from the SCA page at www.feta.co.uk
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 54
Pressurisation
Systems
Ventilation In Car
Parks– Performnce testing
Q&A Session…
“People feel better in Colt conditions” | www.coltgroup.com
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Colt International Ltd
Smoke and environmental ventilation of multi-storey buildings using shafts
Colt Technical Seminar
“People feel better in Colt conditions” | www.coltinfo.co.uk
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 2
A brief history of Colt
•
A private company founded in 1931
•
I J O’Hea OBE (1897 - 1984)
•
2014 Group turnover £146 million
•
Manufactures in the UK, Holland, Germany and China
I J O’Hea
Colt Founder
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 3
Current UK Business Markets
•
Smoke Control
•
Solar Shading
•
Natural Ventilation
•
Louvre
•
Environmental Comfort Control
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 4
Ventilation using shafts – covering:
1.
Ventilation of Fire Fighting Stairs:
• Natural Ventilation to BS 5588 Part 5 and BS 9999
• Natural Shafts to BS 5588 Part 5 and BS 9999
• BRE Shafts to BS 5588 Part 5 and BS 9999
• Mechanical Shafts
2.
Ventilation of Common Corridors in Residential Developments:
• Natural Ventilation to ADB 2006 and BS 9991
• Natural Shafts to ADB 2006 and BS 9991
• Mechanical Ventilation to ADB 2006
3.
Extended Travel Distances in Common Corridors Using Mechanical Shafts
4.
Day to day ventilation and cooling
5.
Pressurisation
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 5
Ventilation using shafts - general
Description:
•
A common shaft passing through multiple levels allowing natural or mechanical ventilation to
the fire floor via the use of dampers or automatic opening devices on each level.
Used for:
•
•
Ventilating fire fighting lobbies to assist fire fighting operations from a fire fighting shaft
and/or
Ventilating common corridors in high rise residential developments.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 6
Ventilation using shafts
1.
Ventilation of fire fighting stairs
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 7
Ventilation using shafts
1.
Ventilation of fire fighting stairs
Fire Fighting:
In fire fighting shafts the fire and rescue services need clear access to every level.
Usual fire fighting protocol is to take the lift to a floor below the fire floor, connect to the dry riser
and then ascend to the fire floor by stair.
The primary objectives of the ventilation system are, therefore:
•
•
to prevent smoke spread into the staircase
to improve conditions in the fire fighting lobby
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 8
Ventilation using shafts
1.
Ventilation of fire fighting stairs
BS 5588 Part 5 and BS 9999 provide prescriptive ventilation recommendations
Stairwell ventilation
•
•
A 1.5m2 openable vent
at the head of the stairwell; or
Lobby ventilation
•
A 1m2 vent (OV) in the fire fighting lobby; or
•
A 3m2 shaft with 1.5m2 dampers on each level
with openings at the top and bottom of the shaft;
or
•
The BRE Method, which is as above, but omits the
opening at the bottom of the shaft.
A 1m2 openable window at each storey
(OV)
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 9
Ventilation using shafts
1.
Ventilation of fire fighting stairs – BRE shaft
•
A 3m2 shaft is connected to the lobbies by
1.5m2 dampers at high level. Only the damper
on the fire floor opens
•
Air inlet is provided via the stairs from the final
exit door and a 1m2 ventilator at the head of
the stairs
•
No air inlet is required at the base of the shaft
– replacement air is drawn from the staircase,
preventing smoke flow into the stair.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 10
Ventilation using shafts
1.
Ventilation of fire fighting stairs – BRE shaft
Visibility in onerous
wind conditions
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 11
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The next obvious step
•
Offers a further reduction in the occupied space taken up by the
system
•
If effective could be used for both fire fighting and means of escape
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 12
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The major challenge is to avoid excessive depressurisation of the lobby to prevent smoke
being drawn in and problems opening doors
This can be avoided by:
Fire Fighting Lobby
negative
•
•
•
•
•
Low level inlet
An inlet shaft
Doors to be open
Grilles in doors
Variable speed fans
Staircase
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 13
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
We developed a standard system that is at least as good as
the BRE smoke shaft and better in adverse wind conditions
•
The system comprises:
-
a small vertical shaft 0.6m2 instead of 3.0m2
a variable speed extract fan set (run and standby)
a pressure sensor in each lobby
a small motorised damper to each lobby
a 1m2 stairwell ventilator
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 14
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 15
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
•
The design has been proven by CFD analysis
•
By replicating the BRE shaft CFD analysis after discussion with BRE
•
By optimising the air flow rate and shaft and damper dimensions to match the BRE shaft
By modelling closed door conditions to ensure that the system:
•
Does not draw excess smoke into the lobby with doors closed (smoke seal doors between lobby
and accommodation are needed for this)
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 16
Ventilation using shafts
1.
Ventilation of fire fighting stairs – Colt shaft
Visibility - doors open
Mechanical shaft
BRE shaft
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 17
Ventilation using shafts
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 18
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
In multi-storey residential buildings, the main escape route is via common corridors and/or
lobbies to protected stairs.
Smoke will spread to the corridor from a fire in an apartment as the occupants make their
escape.
The 2006 version of ADB requires common corridors or lobbies which open onto a stair to be
ventilated. Fire fighting stairs in residential buildings do not require a separate ventilated fire
fighting lobby.
The ventilation system allows the smoke in the corridor to be cleared and ensures that smoke is
prevented from entering the staircase, which could make make escape difficult for occupants of
higher storeys should the whole building need to be evacuated.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 19
Ventilation using shafts
Small single stair apartment buildings
•
Top floor level no more than 11m above ground level
•
No more than 3 storeys above ground level
•
Stair does not connect to covered car park
ADB Requires:
• Openable vent (OV) to each landing level of stair or single OV at head of stair with activation
from bottom of stair.
Also:
• If lobby is ventilated, travel distance from apartment to stair can be increased from 4.5 to
7.5m.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 20
Ventilation using shafts
All other apartment buildings
ADB Requires:
• All corridors/lobbies adjoining stairs to be ventilated
by either natural or mechanical means.
•
The staircase requires a vent with a free area of 1.0m2 from the top storey to outside.
Activation:
• In a single stair building, the vents should be automatic via smoke detectors in the common
access space.
•
In a multi-stair building, the ventilation can be manual, BUT the vent at the top of the stair
must be interlinked to open at the same time.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 21
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Common Corridors can be ventilated, either:
•
Naturally, located on an outside wall with a minimum free area of 1.5m2
•
Naturally, discharged into a vertical smoke shaft, closed at the base
•
Mechanically, using extract and natural inlet or supply fans
•
Mechanically, using pressure differentials, in accordance with BS EN 12101-6: 2005
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 22
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural ventilation
SHAFT
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 23
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Minimum free area under the 2000 edition of ADB
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 24
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Definition of Minimum Free Area, either:
The aerodynamic free area of the ventilator as defined in EN
12101 Part 2: 2003 – Specification for natural smoke and heat
exhaust ventilators.
Or:
"the total unobstructed cross sectional area, measured in the
plane where the area is at a minimum and at right angles to the
direction of air flow"
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 25
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Minimum free area under the 2006 edition of ADB
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 26
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
If a shaft system is used, the following criteria should be met:
The Shaft should:
•
•
•
•
Be closed at the base
Have a minimum cross-sectional area of 1.5m2 with a minimum dimension of 0.85m in either
direction.
Extend at least 0.5m above the highest structure within 2m
Extend 2.5m above the ceiling of the highest level served by the shaft.
The vent into the shaft, the vent at the top of the shaft and any safety grilles in the shaft should all
have a minimum free area of 1.0m2.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 27
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Construction:
The shaft should be constructed from non-combustible material and the vents should be
equivalent to a E30Sa fire door.
The shaft should be vertical with no more than 4m at an inclined angle (max 30o)
Operation:
On detection of smoke in the corridor, the vent on the fire floor, at the top of the shaft and the
top of the stair should all open simultaneously – vents on all other levels should remain closed.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 28
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Exhaust opening
Ventilation damper
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 29
Ventilation using shafts
2.
Ventilation of common corridors in residential developments
Typical Roof Installation
Natural Ventilation
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 30
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Internal Damper to shaft, concealed by decorative grille :
•
Equivalent to E30S Fire
rated construction
•
Motor open/closed
•
Natural, minimum free
area 1.0m2
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 31
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Colt Doorman Actuator with fire door to shaft:
•
Equivalent to E30S Fire rated
construction
•
Require a safety grille across shaft at
each level
•
Units on other levels must lock closed
to prevent smoke transfer
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 32
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – natural shafts
Approved Document B permits the use of mechanical ventilation for smoke control of
common escape routes but gives no design guidance on how to design such a system.
However based on the experience gained in developing the Colt Shaft for fire fighting
applications, several options are available to reduce the natural shaft from 1.5m2 to 0.6m2
using a mechanical system.
As with the fire fighting system, the main objective is to keep smoke from entering the
staircase.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 33
Ventilation using shafts
2.
Ventilation of common corridors in residential developments – mechanical shafts
Internal Damper to shaft, concealed by decorative grille or flap vent:
•
Equivalent to E30S Fire rated
construction
•
Motor open/closed
•
Mechanical - Typically 0.8m2
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 34
Ventilation using shafts
3.
Means of escape systems – extended travel
An extended lobby can be used to reduce travel, but the lobby “..must not provide direct
access to any storage room, flat or other place containing a potential fire hazard.”
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 35
Ventilation using shafts
3.
Means of escape systems – extended travel
ADB 2006 states: “There may be some instances where some increase on these maximum
figures [travel distances] will be reasonable.” In most circumstances mechanical systems
can be designed to enhance safety.
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 36
Ventilation using shafts
3.
Means of escape systems – extended travel
Options:
•
Natural Exhaust/Mechanical Inlet
•
Mechanical Extract/Natural Inlet
•
Mechanical Extract/Mechanical Inlet
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 37
Ventilation using shafts
3.
Means of escape systems – extended travel
Natural Exhaust/Mechanical Inlet
Has been used by various fire engineers with varying degrees of success.
Positively pressurises the corridor, therefore can risk pushing smoke into other apartments and
staircase.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 38
Ventilation using shafts
3.
Means of escape systems – extended travel
Natural Exhaust/Mechanical Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 39
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
Slightly depressurises the corridor, therefore inlet shaft and dampers need to be
sized carefully to avoid creating a pressure greater than 50 Pa.
Typically, inlet shaft will need to be in order of 1.5m2.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 40
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 41
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Natural Inlet
•
On one typical project the Travel Distance was successfully extended from 7.5m to
18m in one direction
•
System modelled in both escape and fire-fighting mode and compared with a
compliant corridor with a natural AOV system.
•
System out-performs natural AOV for both evacuation and for fire-fighting
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 42
Ventilation using shafts
3.
Means of escape systems – extended travel
Modelled to compare with compliant 7.5m corridor with AOV in still wind conditions with
growing fire in apartment.
Smoke spills into corridor during evacuation and then again 10 minutes later when fire
brigade arrive, fire has grown to around 5000 kW
Compliant Corridor
Extended Corridor
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 43
Ventilation using shafts
3.
Means of escape systems – extended travel
Compliant AOV
Extended Mechanical System
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 44
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
Reduces size of inlet shaft to 0.6m2 typically.
Extract to be designed as Colt Shaft without pressure sensing, inlet fan to match
extract rate.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 45
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
7.5m+
7.5m
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 46
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet
Reversible
•
Particularly useful with a central stair to two extended corridors.
•
Fans need to be truly reversible (standard fans run at approx 60% in reverse), or
additional inlet may be necessary.
•
Detection needs to identify smoke location.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 47
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet Reversible
7.5m+
7.5m
7.5m
7.5m+
A further benefit of this system is that fire fighters can override the system so that both fan
systems can be set to extract, allowing an enhanced clearance system.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 48
Ventilation using shafts
3.
Means of escape systems – extended travel
Mechanical Extract/Mechanical Inlet Reversible
Smoke can be controlled depending
on the fire location
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 49
Ventilation using shafts
4.
What can we do to avoid corridors overheating?
What can we do to avoid corridors overheating?
Supply
Extract
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 50
Ventilation using shafts
4.
Day to day ventilation
Cooling?
A ventilation system based on
supplying outside air alone is able
to achieve temperatures in the
corridor typically 2-5oC above the
outside ambient.
Adiabatic cooling can reduce
supply temperatures well below
outside ambient, providing active
cooling in the corridors.
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 51
Ventilation using shafts
5.
Pressurisation
•
Supply air
•
Distribution Ductwork
•
Pressure Relief
•
Air Release
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 52
Ventilation using shafts
5.
Pressurisation
•
Optimum protection
•
Expensive
•
Complex design
•
Puts more demands on quality of building construction
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 53
Ventilation using shafts
Conclusions
The work of the BRE resulted in alternative methods of ventilation being considered, which have
been incorporated into Approved Document B.
This has paved the way for many new developments in the use of mechanical ventilation shafts in
numerous applications.
•
If space is tight and a shaft system is needed, a mechanical shaft is the solution
•
If dead end corridor lengths exceed prescriptive limits, a mechanical shaft system with
improved performance is the solution
•
Further guidance can be found in a free Smoke Control Association guide, downloadable
from the SCA page at www.feta.co.uk
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk
Slide 54
Pressurisation
Systems
Ventilation In Car
Parks– Performnce testing
Q&A Session…
“People feel better in Colt conditions” | www.coltgroup.com
“People
“Peoplefeel
feelbetter
betterininColt
Coltconditions”
conditions” | |www.coltgroup.com
www.coltinfo.co.uk