Download Report

Module 7
Control of Smoke & Highlights of Code
Requirements
1
Module 7 Overview
This module will cover:
1. The requirements of smoke control in the Ohio Building Code
Section 909
2. The differences between active and passive systems
3. The components of a smoke control system
4. The requirements of smoke and heat vents per Section 910 OBC.
5. The differences between the mechanical and manual activation of
smoke exhaust systems
2
Smoke Control Systems
•
An engineered system that
includes all methods that can be
used singly or in combination to
modify smoke movement
•
Two types:
•
•
•
Passive
Active
NFPA Standards
•
92B-09: Standard for Smoke
Management Systems in Malls,
Atria, and Large Spaces
3
Smoke Control Systems: Passive
•
Any portion of a building or structure that provides protection
from smoke without any type of system activation or
movement.
•
Use compartmentalization, reservoirs or other methods to
control smoke to a predetermined habitable level
•
Utilized when active control systems are not feasible and/or to
help them function
• Relies on the natural buoyancy of the smoke and the stack
effect to allow the smoke to exit the building.
4
Smoke Control Systems: Passive
High Bay/ High Ceilings
• Act as a reservoir to contain smoke
Natural ventilation
•
The flow of air or gases created by the difference in the
pressures or gas densities between the outside and inside of a
vent, room, or space.
•
Open exterior balcony or vestibule with opening 16 sq. ft. in
area facing an open area that is at least 20 ft. in width.
5
Smoke Control Systems: Passive
Operable or “break-out” windows
Operable window
• Manually controlled
Fusible Link Operated Vent
•
A fusible link holds open springloaded fire-rated damper
•
The link is designed to melt at a
certain temperature
•
When it melts the damper slams shut.
6
Smoke Control Systems: Active
•
A system that uses moving mechanical or electrical parts to
achieve a smoke control goal.
•
Also known as mechanical
•
Preferred method of smoke control
7
Smoke Control Systems: Active
Exhaust
•
Air removed from a space or power
system and not reused.
•
•
Pulls smoke from space
Utilizes:
•
•
•
Automatic detection
Exhaust fans
Make up air
Colt International Ltd
8
Smoke Control Systems: Active
• Pressurization
• Uses wall and floor assemblies
•
•
with pressure difference
Fans create the pressure
difference
Default design method in the IBC
Indiana University of Pennsylvania
9
Smoke Control Systems: Active
Airflow
• Large airflows from adjacent compartments to fire
compartment
•
•
•
Difficult to achieve
Typically utilizes air-moving device
Most commonly used to stop smoke movement through open
doorways and corridors
10
Smoke Control Systems:
Components
Figure 702.1(11) SMOKE BARRIER
Smoke barrier
• A continuous membrane, or a
membrane with discontinuities created
by protected openings, where such
membrane is designed and constructed
to restrict the movement of smoke.
• Smoke zone: The smoke control zone in
which the fire is located.
• NFPA Standards
• 92B-09: Standard for Smoke
International Building Code Commentary
Management Systems in Malls,
Atria, and Large Spaces
11
Smoke Control Systems: Components
Control panel
• Intended to communicate
•
with fire fighters
Installed in approved location
adjacent to fire alarm panel
KMC Controls, Inc.
12
Smoke Control Systems: Components
Power supply
•
The system is supplied with two sources of power
• Primary power shall be from the normal building power systems.
•
Secondary power shall be from an approved standby source
complying with Chapter 27 of the Building Code.
13
Smoke Control Systems: Components
Smoke detector
• A device that detects visible or
•
invisible particles of combustion
issue a signal to a fire alarm
control panel as part of a fire
alarm system
Wikimedia Commons
14
Smoke Control Systems: Components
Fans
• A blower or exhauster assembly comprising
blades or runners and housings or casings.
•
Examples
•
•
Pressurization
Exhaust
Colt Group Ltd/
15
Smoke Control Systems: Components
Ducts
• Pipes, tubes, or other enclosures used for the purpose of
pneumatically conveying materials
•
Examples
•
•
Exhaust
Supply
LifeSafety Magazine
16
Smoke Control Systems: Components
Make-up air inlets
•
Controlled air vents that allow for
fresh, draft-free make-up air to
enter a building.
•
Make-up air is provided for exhaust
systems
•
Replaces the air that is removed
Luxury Metals LLC
17
Smoke Control Systems: Components
Smoke Dampers
• A device within an air distribution system
to control the movement of smoke
•
Closes upon actuation of a listed smoke
detector or detectors
Wikimedia Commons
18
Smoke and Heat Vents
•
Openings in the roof which are
intended to vent the heat and
smoke developed by a fire
inside the building
• NFPA Standards:
• 204: Standard for Smoke and
Heat Venting
•
for information only, not
listed in chapter 35 OBC
Smye Holland Associates Limited
19
Unit-type vents
•
Small openings on a structure’s roof, equipped with a metal
frame and housing and manual or automatic hinged dampers,
which are opened in case of fire.
• Using mechanical openings
• Using gravity openings
20
Unit-type vents
Using mechanical openings
•
A small openings on a structure’s
roof, equipped with a metal frame
and housing and automatic hinged
dampers, which are opened in case
of fire.
• Spring lift
• Pneumatic lift
• Electric motor-driven lift
National Domelight Company
21
Unit-type vents
Using mechanical openings:
Spring
• Tension is maintained on a
•
fusible link with the use of a
heavy duty spring.
High temperatures melt the
fusible link
Santa Barbara County Fire Dept
22
Unit-type vents
Using mechanical openings:
Pneumatic Lift
•
uses a pressurized air system to open the vent automatically
with a loss, or activation, of air pressure
Babcock-Davis
23
Unit-type vents
Using mechanical openings:
Electric motor-driven lift
•
equipped with electrical links that trigger the vent opening when
connected to a remote smoke or fire alarm.
FAKRO
24
Smoke and Heat Vents:
Unit-type vents
Using gravity openings:
Plastic shrink-out panels
• Constructed of plastic which
shrinks in the presence of heat
• drop-out panel
HPAC Engineering
25
Mechanically-powered venting systems
•
•
Consists of fixed, motor-driven fans that can be mounted on the
roofs
Rely on mechanical extraction of smoke through fans.
Energy Vanguard's
26
Glass roof and continuous gravity vents
•
Ordinary glass roof vents
• Vents in glass roofs
•
Continuous gravity vents (ridge vents)
• Installed at the peak of a sloped roof which allows smoke to
escape a building's attic.
27
Mechanical smoke- exhaust systems
•
A dedicated or shared-duty fan system
designed and suitable for the removal of
heat and smoke.
•
May be an acceptable alternative to
smoke and heat vents.
Colt International Licensing Ltd
28
Manually-activated smoke exhaust systems
• Operated by the fire department
• Are an acceptable alternate to smoke and heat vents
29
Why are smoke control systems are required?
•
•
To improve conditions in common areas to facilitate safe
escape for occupants when a fire occurs
To enable the fire to be fought in its early stages
30
When are smoke control systems required?
•
1. Determine the location of the top floor above ground
floor level
•
•
2. The nature of occupancy
3. Location of the building above the fire service access
level, then a fire fighting core(s) is required.
31
Codes and Standards: OBC
•
404.5 Smoke Control- Atriums
•
402.10 Smoke Control- Covered
malls and other mall buildings
Wikimedia Commons
32
Codes and Standards: OBC
•
1028.6.2.1 Smoke Control- Means of egress
•
410.3.7.2 Smoke Control- Stages
•
403.5.4 Smoke Control- High Rise Buildings
33
Codes and Standards: OBC
• 405.5 Smoke Control- Underground Buildings
• 415.7.5.3 Smoke Control- Groups H-3 and H-4
• 909.4 Analysis
34
Codes and Standards: OBC
•
•
•
•
909.6 Pressurization Methods
909.7 Airflow Design Method
909.8 Exhaust Method
909.19 System Acceptance
35
Codes and Standards: OBC
•
•
•
909.8 Exhaust Method
909.19 System Acceptance
909.18.8 Special Inspection for smoke control
Wikimedia Commons
36
Codes and Standards: OBC
•
•
•
1704.16 Special Inspection for Smoke Control
910.2 Smoke and heat vents- Where required
910.3 Design and installation
37
Codes and Standards: OBC
•
•
•
•
910.3.2 Vent operation
910.3.2.2 Sprinklered buildings
910.3.2.3 Nonsprinklered buildings
910.3.3 Vent dimensions
Wikimedia Commons
38
Codes and Standards: OBC
•
•
•
•
910.3.5 Draft curtains
910.4 Mechanical smoke exhaust
910.5 Manually activated smoke exhaust system
1016.3 Group F-1 and S-1 increase maximum travel distance
39
Codes and Standards: OFC
Chapter 23: High-Piled Combustible
Storage
• High piled storage in excess of 12 feet
requires specific consideration,
including fire protection design
features and smoke and heat vents in
order to be adequately protected.
• Not all high-piled storage will require
the use of smoke and heat vents and
draft curtains. If properly sprinklered,
draft curtains aren’t required.
Fairfax County Va.
40
Code and Standards: NFPA
92B: Smoke Management Systems in Malls, Atria, and Large Spaces
• This standard provides methodologies for estimating the
location of smoke within a large-volume space due to a fire
either in the large-volume space or in an adjacent space.
41
Lessons learned in Module 7
1. There are two types of smoke control systems, passive and active.
2. Smoke control systems must be supplied with two sources of power.
3. Smoke control systems are designed to improve conditions in common
areas, to facilitate safe escape for occupants when a fire occurs, and to
enable the fire to be fought in its early stages
4. Unit type vents are small openings on a structure’s roof, equipped with
a metal frame and housing and manual or automatic hinged dampers,
which are opened in case of fire.
5. Chapter 23 of the Ohio Fire Code regulates high piled combustible
storage.
42