module 7 - ohio board of building standardsohiobbseducation.com/workbook/module 7 bbs2015-...

Control of Smoke & Highlights of Code Requirements

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Module 7

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

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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

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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.

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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.

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Operable or “break-out” windows

• Manually controlled

Fusible Link Operated Vent

• A fusible link holds open spring-loaded fire-rated damper

• The link is designed to melt at a certain temperature

• When it melts the damper slams shut.

Operable window

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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

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Exhaust

• Air removed from a space or power system and not reused.

• Pulls smoke from space

• Utilizes:

• Automatic detection

• Exhaust fans

• Make up airColt International Ltd

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• Pressurization

• Uses wall and floor assemblies with pressure difference

• Fans create the pressure difference

• Default design method in the IBC

Indiana University of Pennsylvania

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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

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Smoke Control Systems: Components

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

Management Systems in Malls, Atria, and Large Spaces

Figure 702.1(11) SMOKE BARRIER

International Building Code Commentary

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Control panel

• Intended to communicate with fire fighters

• Installed in approved location adjacent to fire alarm panel

KMC Controls, Inc.

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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.

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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

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Fans

• A blower or exhauster assembly comprising blades or runners and housings or casings.

• Examples

• Pressurization

• Exhaust

Colt Group Ltd/

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Ducts

• Pipes, tubes, or other enclosures used for the purpose of pneumatically conveying materials

• Examples

• Exhaust

• Supply

LifeSafety Magazine

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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

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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

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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

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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

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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 liftNational Domelight Company

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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

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Unit-type vents


Pneumatic Lift

• uses a pressurized air system to open the vent automatically with a loss, or activation, of air pressure

Babcock-Davis

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Unit-type vents


Electric motor-driven lift

• equipped with electrical links that trigger the vent opening when connected to a remote smoke or fire alarm.

FAKRO

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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

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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

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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.

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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

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Manually-activated smoke exhaust systems

• Operated by the fire department

• Are an acceptable alternate to smoke and heat vents

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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

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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.

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Codes and Standards: OBC

• 404.5 Smoke Control- Atriums

• 402.10 Smoke Control- Covered malls and other mall buildings

Wikimedia Commons

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• 1028.6.2.1 Smoke Control- Means of egress

• 410.3.7.2 Smoke Control- Stages

• 403.5.4 Smoke Control- High Rise Buildings

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• 405.5 Smoke Control- Underground Buildings

• 415.7.5.3 Smoke Control- Groups H-3 and H-4

• 909.4 Analysis

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• 909.6 Pressurization Methods

• 909.7 Airflow Design Method

• 909.8 Exhaust Method

• 909.19 System Acceptance

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• 909.8 Exhaust Method

• 909.19 System Acceptance

• 909.18.8 Special Inspection for smoke control

Wikimedia Commons

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• 1704.16 Special Inspection for Smoke Control

• 910.2 Smoke and heat vents- Where required

• 910.3 Design and installation

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• 910.3.2 Vent operation

• 910.3.2.2 Sprinklered buildings

• 910.3.2.3 Nonsprinklered buildings

• 910.3.3 Vent dimensions

Wikimedia Commons

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• 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

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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.

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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.

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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.

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module 7 - ohio board of building standardsohiobbseducation.com/workbook/module 7 bbs2015-...

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