MEEB Chapter 13 - FIRE PROTECTION

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• annunciator

In large buildings, a central fire alarm annunciator panel is located where it is accessible to fire-fighting crews. The annunciator panel will indicate the zone and approximate physical location of the source of a fire alarm in the building. The annunciator will also include lamps and audible warning devices to indicate failures of alarm circuits. In a large building such as an office tower or hotel, the fire annunciator may also be associated with a control panel for building ventilation systems, and may also include emergency communication systems for the building.

Heat detector

Use in Heat Stage: uncontrolled heat and rapidly expanding air.

Water spray

"Water spray" systems are operationally identical to a deluge system, but the piping and discharge nozzle spray patterns are designed to protect a uniquely configured hazard, usually being three-dimensional components or equipment (i.e., as opposed to a deluge system, which is designed to cover the horizontal floor area of a room). The nozzles used may not be listed fire sprinklers, and are usually selected for a specific spray pattern to conform to the three-dimensional nature of the hazard (e.g., typical spray patterns being oval, fan, full circle, narrow jet). Examples of hazards protected by water spray systems are electrical transformers containing oil for cooling or turbo-generator bearings. Water spray systems can also be used externally on the surfaces of tanks containing flammable liquids or gases (such as hydrogen). Here the water spray is intended to cool the tank and its contents to prevent tank rupture/explosion (BLEVE) and fire spread.

• fire stage

(incipient, smoldering, flame, heat)

• photoelectric smoke detector

(spot, projected beam, scattered light, laser beam)

• sprinkler head

(upright, pendant, sidewall; recessed, flush, concealed, ornamental; ordinary, quick-response, flow control)

• coded

(zone, master, dual, selective, or noncoded)

Three approaches to lightning protection

-The franklin cone is provided by a central mast that acts as air terminal, conductor and ground. -The overhead ground shield wire provides a triangular prism protection zone. -The Faraday cage wraps a protective mesh around the structure.

• smoke barrier

711.9 Smoke barrier. Where horizontal assemblies are required to resist the movement of smoke by other sections of this code in accordance with the definition of smoke barrier, penetrations and joints in such horizontal assemblies shall be protected as required for smoke barriers in accordance with Sections 714.5 and 715.6. Regardless of the number of stories connected by elevator shaft enclosures, doors located in elevator shaft enclosures that penetrate the horizontal assembly shall be protected by enclosed elevator lobbies complying with Section 713.14.1. Openings through horizontal assemblies shall be protected by shaft enclosures complying with Section 713. Horizontal assemblies shall not be allowed to have unprotected vertical openings.

Overhead ground shield wire

A continuous air terminal, this shield is linear and horizontal, so the protected volume is a triangular prism rather than a cone. this is most commonly used to protect overhead transmission lines.

• conventional fire detection device (and system)

A conventional system employs one or more initiating circuits, connected to sensors (initiating devices) wired in parallel. These sensors are devised to decrease the circuits resistance when the environmental influence on any sensor exceeds a predetermined threshold. In a conventional system the information density is limited to the number of such circuits used. At times, a floor plan of the building is often placed near the main entrance with the defined zones drawn up, and LEDs indicating whether a particular circuit/zone has been activated. Another common method is to have the different zones listed in a column, with an LED to the left of each zone name.

• false alarm

A false alarm, also called a nuisance alarm, is the deceptive or erroneous report of an emergency, causing unnecessary panic and/or bringing resources (such as emergency services) to a place where they are not needed. False alarms may occur with residential burglary alarms, smoke detectors, industrial alarms, and in signal detection theory. False alarms have the potential to divert emergency responders away from legitimate emergencies, which could ultimately lead to loss of life. In some cases, repeated false alarms in a certain area may cause occupants to develop alarm fatigue and to start ignoring most alarms, knowing that each time it will probably be false. The concept of this can be traced at least as far back as Aesop's story of The Boy Who Cried Wolf, where many episodes of a boy falsely yelling "wolf" caused the townspeople to ignore his cries when a real wolf came.

• strobe

A fire alarm notification appliance is an active fire protection component. A notification appliance may use audible, visible, or other stimuli to alert the occupants of a fire or other emergency condition requiring action. Audible appliances have been in use longer than any other method of notification. Most of today's appliances produce sound pressure levels between 45 and 120 decibels at ten feet.

• street siamese

A fire hydrant is an active fire protection measure, and a source of water provided in most urban, suburban and rural areas with municipal water service to enable firefighters to tap into the municipal water supply to assist in extinguishing a fire.

• fire pump

A fire pump is a part of a fire sprinkler system's water supply and can be powered by electric, diesel or steam. The pump intake is either connected to the public underground water supply piping, or a static water source (e.g., tank, reservoir, lake). The pump provides water flow at a higher pressure to the sprinkler system risers and hose standpipes. A fire pump is tested and listed for its use specifically for fire service by a third-party testing and listing agency, such as UL or FM Global. The main code that governs fire pump installations in North America is the National Fire Protection Association's NFPA 20 Standard for the Installation of Stationary Fire Pumps for Fire Protection.[1]

Foam water sprinkler systems

A foam water fire sprinkler system is a special application system, discharging a mixture of water and low expansion foam concentrate, resulting in a foam spray from the sprinkler. These systems are usually used with special hazards occupancies associated with high challenge fires, such as flammable liquids, and airport hangars. Operation is as described above, depending on the system type into which the foam is injected.

• thermal or temperature detector (spot, linear)

A heat detector is a fire alarm device designed to respond when the convected thermal energy of a fire increases the temperature of a heat sensitive element. The thermal mass and conductivity of the element regulate the rate flow of heat into the element. All heat detectors have this thermal lag. Heat detectors have two main classifications of operation, "rate-of-rise" and "fixed temperature."

• lightning arrester

A special type of surge arrester, a lightning arrester is generally connected at one end to an overhead electrical line and at the other end to the ground. It thus suppresses any lightning voltage surges that appear in the electrical line, so that equipment downstream on that line is not damaged.

smokeproof tower

A stairwell which provides with direct access to outdoor air at each floor level and which meets the requirements of the applicable code. Under United States building codes, the stairwell of a smokeproof enclosure must have walls with a 2 hour fire resistance rating and vestibule doors (if provided) with a 1.5 hour fire resistance rating.

• addressable fire detection device (and system)

Addressable Fire Alarm Control Panels employ one or more Signaling Line Circuits, slang - usually referred to as loops or SLC loops - ranging between one and thirty. Depending on the protocol used, a Signaling Line Circuit can monitor and control several hundred devices. Some protocols permit any mix of detectors and input/output modules, while other protocols have 50% of channel capacity restricted to detectors/sensors and 50% restricted to input/output modules. Each SLC polls the devices connected, which can number from a few devices to several hundred, depending on the manufacturer. Large systems may have multiple Signaling Line Circuits.[1][2]

• air sampling detector

An air-sampling smoke detector is capable of detecting microscopic particles of smoke. Most air-sampling detectors are aspirating smoke detectors, which work by actively drawing air through a network of small-bore pipes laid out above or below a ceiling in parallel runs covering a protected area. Small holes drilled into each pipe form a matrix of holes (sampling points), providing an even distribution across the pipe network. Air samples are drawn past a sensitive optical device, often a solid-state laser, tuned to detect the extremely small particles of combustion. Air-sampling detectors may be used to trigger an automatic fire response, such as a gaseous fire suppression system, in high-value or mission-critical areas, such as archives or computer server rooms.

• intumescent material

An intumescent is a substance that swells as a result of heat exposure, thus increasing in volume and decreasing in density. Intumescents are typically used in passive fire protection and, in the U.S., require listing and approval use and compliance in their installed configurations in order to comply with the law.

clean agent fire suppression system

Argon is a clean agent fire suppression system, ideal for use in areas containing valuable equipment that could be damaged by water. It is an inert gas that is completely safe both for humans and the environment. Because Argon is non-corrosive and does not produce any toxic by-products, no down time will occur due to discharge. With Argon, there is no chance of a future ban, as with Halon. Applications: Suitable for use on Class A, B, and C fires. A few applications that benefit the most from an argon fire protection system are telecom switch gear enclosures, remote cell sites, computer and server rooms, archives, machine tools, electrical generator enclosures, and art galleries.

• automatic fire suppression

Automatic fire suppression systems control and extinguish fires without human intervention. Examples of automatic systems include fire sprinkler system, gaseous fire suppression, and condensed aerosol fire suppression.

• automatic ventilating hatch

Automatic smoke vents aid Firefighters in bringing a fire under control by removing smoke, heat and gasses from a burning building. Type SV single leaf smoke vents are ideal for applications requiring smaller vent areas, such as elevator shafts or stair wells. Available in galvanized steel or aluminum construction and in a number of standard sizes. Polycarbonate domes covers are also available for natural daylighting.

• wet-pipe

By a wide margin, wet pipe sprinkler systems are installed more often than all other types of fire sprinkler systems. They also are the most reliable, because they are simple, with the only operating components being the automatic sprinklers and (commonly, but not always) the automatic alarm check valve. An automatic water supply provides water under pressure to the system piping.

carbon dioxide

Carbon dioxide is produced during the processes of decay of organic materials and the fermentation of sugars in beer and winemaking. It is produced by combustion of wood, carbohydrates and major carbon- and hydrocarbon-rich fossil fuels such as coal, peat, petroleum and natural gas. It is emitted from volcanoes, hot springs and geysers and is freed from carbonate rocks by dissolution in water and acids. CO2 is found in lakes, at depth under the sea and commingled with oil and gas deposits.[4]

carbon monoxide

Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air. It is toxic to humans when encountered in concentrations above about 35 ppm, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions. In the atmosphere, it is spatially variable and short lived, having a role in the formation of ground-level ozone.

• computational fluid dynamics (CFD)

Computational fluid dynamics, usually abbreviated as CFD, is a branch of fluid mechanics that uses numerical methods and algorithms to solve and analyze problems that involve fluid flows. Computers are used to perform the calculations required to simulate the interaction of liquids and gases with surfaces defined by boundary conditions. With high-speed supercomputers, better solutions can be achieved. Ongoing research yields software that improves the accuracy and speed of complex simulation scenarios such as transonic or turbulent flows. Initial experimental validation of such software is performed using a wind tunnel with the final validation coming in full-scale testing, e.g. flight tests.

Ionization Detector

Contain a small amount of radioactive material that serves to ionize the air between two charged surfaces, causing a current to flow. Also use during Incipient Stage

dry-pipe

Dry pipe systems are installed in spaces in which the ambient temperature may be cold enough to freeze the water in a wet pipe system, rendering the system inoperable. Dry pipe systems are most often used in unheated buildings, in parking garages, in outside canopies attached to heated buildings (in which a wet pipe system would be provided), or in refrigerated coolers. Dry pipe systems are the second most common sprinkler system type. In regions using NFPA regulations, dry pipe systems cannot be installed unless the range of ambient temperatures reaches above 40F.[13]

• halogenated hydrocarbon (halon)

Halogenated fire extinguishing systems contain a Halon agent that inhibits the chemical reaction of fuel and oxygen, thus stopping the combustion chain reaction.

• presignaling

In "presignal" systems, activation of the fire alarm system does not sound an alarm throughout the building immediately. There is either a built-in delay of at least 1 minute from system activation or the initial fire alarm signals sound only in department offices, control rooms, fire brigade stations, or other constantly attended central locations. Then, someone must intervene to sound a general fire alarm.

• analog fire detection device

Instead of the systems now being installed using the old zone radial circuits, fire alarms now began to be wired using loop circuits, where large amounts of fire alarm system devices could be incorporated onto each loop of the fire alarm system. This was a great advantage to fire alarm installation companies as instead of having to bring each zone circuit back to the panel position they could now wire multiple zones around the loop before having to come back to the panel position. This saved installation time and also has a great cost benefit in the reduced amount of cable needed to wire the same amount of devices.

• fire spandrel

Joints installed in or between fire-resistance-rated walls, floor or floor/ceiling assemblies and roofs or roof/ceiling assemblies shall be protected by an approved fire-resistant joint system designed to resist the passage of fire for a time period not less than the required fire-resistance rating of the wall, floor or roof in or between which it is installed. Fire-resistant joint systems shall be tested in accordance with Section 715.3.

Franklin Cone

Named for Ben Franklin, is simply a mast with a conductor running straight to ground. A "cone of protection" is formed that protects the objects within in from strikes by absorbing the lightning stroke at the mast and grounding it harmlessly.

preaction

Pre-action sprinkler systems are specialized for use in locations where accidental activation is undesired, such as in museums with rare art works, manuscripts, or books; and Data Centers, for protection of computer equipment from accidental water discharge. Pre-action systems are hybrids of wet, dry, and deluge systems, depending on the exact system goal. There are two main sub-types of pre-action systems: single interlock, and double interlock. The operation of single interlock systems are similar to dry systems except that these systems require that a "preceding" fire detection event, typically the activation of a heat or smoke detector, takes place prior to the "action" of water introduction into the system's piping by opening the pre-action valve, which is a mechanically latched valve (i.e., similar to a deluge valve). In this way, the system is essentially converted from a dry system into a wet system. The intent is to reduce the undesirable time delay of water delivery to sprinklers that is inherent in dry systems. Prior to fire detection, if the sprinkler operates, or the piping system develops a leak, loss of air pressure in the piping will activate a trouble alarm. In this case, the pre-action valve will not open due to loss of supervisory pressure, and water will not enter the piping. The operation of double interlock systems are similar to deluge systems except that automatic sprinklers are used. These systems require that both a "preceding" fire detection event, typically the activation of a heat or smoke detector, and an automatic sprinkler operation take place prior to the "action" of water introduction into the system's piping. Activation of either the fire detectors alone, or sprinklers alone, without the concurrent operation of the other, will not allow water to enter the piping. Because water does not enter the piping until a sprinkler operates, double interlock systems are considered as dry systems in terms of water delivery times, and similarly require a larger design area.

• standpipe (automatic-wet, automatic-dry, semiautomatic-dry, manual-dry, manual-wet)

See Quick Response: C:\Users\shih\Dropbox\ARE 4.0\ARE 4.0\5. Building Systems\8. Fire Safety and safety code for elevator and escalators

• ANSI (American National Standards Institute)

The American National Standards Institute (ANSI, /ˈænsiː/ an-see) is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States.[3] The organization also coordinates U.S. standards with international standards so that American products can be used worldwide. For example, standards ensure that people who own cameras can find the film they need for that camera anywhere around the globe.

Faraday Cage

This approach depends on an open interconnected mesh, covering a large nonconducting mass (a building), to draw a lightning stroke and conduct it to Earth. This leaves large areas of the roof exposed, so the higher the air terminals and the denser the mesh, the better the protection.

• central station fire alarm system

This arrangement is similar to that described in Proprietary fire alarm sys. except that the system supervision and normally all of its equipment is owned and operated by a service company.

• protected premises alarm system

This is intended to sound an alarm only in the protected premises. Action in response to an alarm must be taken locally, either manually or automatically. Thus, notification to the fire department must be manual, although fire suppression systems can be set into operation automatically.

• auxiliary fire alarm system

This is simply a local system equipped with a direct connection to a municipal fire alarm box. The received alarm signal is identical to that resulting from a manual alarm at that city box. Since the fire department is aware of all city box connections, arriving firefighters would always check the protected premises. This type of system is usually applied to public buildings such as schools, governmental offices, museums, and the like.

• remote-station protective signaling system

This system is similar to the axuiliary system, except that the alarm or trouble signal is transmitted via a leased telephone line to remote location (a police facility or a telephone answering service) that is manned 24h a day.the notice of alarm is then telephoned to the fire department. this arrangement issued in private buildings, such as stores and offices, that are unoccupied for considerable periods and for which reliance on passersby to turn in a fire signal is unacceptable.

• proprietary fire alarm system

This system, which is applicable to large, multibuilding facilities such as universities, manufacturing facilities, and the like, utilizes a dedicated central supervisory station to receive signals from all buildings.

• circuit supervision

This very common term refers to the circuit arrangements in fire alarm systems that indicates a mulfunction in the wiring of alarm (and other) devices, by sounding a trouble bell. The trouble signal is separate and distinct from an alarm signal.

UV/IRS ( Ultra-violet/Infrared )

UV/IRS ( Ultra-violet/Infrared ) flame detector delivers exceptional performance with many distinct functions and features. Two precise spectrums of radiation must be recognized and confirmed by highly tuned sensors for the UV/IRS to initiate a fire condition. This accurate and reliable flame monitoring technology combined with immunity to arc welding, hot body radiation, lightning and sunlight greatly reduces costly false alarms while providing critical safety performance to your site and personnel.

I/R, U/V Flame detector

Use during flame stage: actual fire now exists. Appreciable heat still not present but follows almost instantaneously.

Photoelectric/ Photoelectronic Detector

Use during smoldering stage - large particles now visible as smoke. Flame or appreciable heat still not present.

• gas-sensing fire detector

Use for Incipient Stage - invisible particulate matter given off. No visible flame smoke or appreciable heat yet present.

• sprinkler alarm

Water flow switches are placed in sprinkler pipelines and operate when a sprinkler head goes off.

Water mist systems

Water mist systems are used for special applications in which it is decided that creating a heat absorbent vapor is the primary objective. This type of system is typically used where water damage may be a concern, or where water supplies are limited. NFPA 750[15] defines water mist as a water spray with a droplet size of "less than 1000 microns at the minimum operation pressure of the discharge nozzle." The droplet size can be controlled by the adjusting discharge pressure through a nozzle of a fixed orifice size. By creating a mist, and equal volume of water will create a larger total surface area exposed to the fire. The larger total surface area better facilitates the transfer of heat, thus allowing more water droplets to turn to steam more quickly. A water mist, which absorbs more heat than water per unit time, due to exposed surface area, will more effectively cool the room, thus reducing the temperature of the flame. Operation - Water mist systems can operate with the same functionality as deluge, wet pipe, dry pipe, or pre-action systems. The difference is that a water mist system uses a compressed gas as an atomizing medium, which is pumped through the sprinkler pipe. Instead of compressed gas, some systems use a high-pressure pump to pressurize the water so it atomizes as it exits the sprinkler nozzle.[16] Systems can be applied using local application method or total flooding method, similar to Clean Agent Fire Protection Systems.

• inerting gas

With the big push toward "Green", inert gasses have become a good choice as they are the most green of all of the Clean Agents. Inert gasses are defined as using one or more of the gasses Nitrogen, argon, or helium. CO2 is also found in one of the inert gas blends. Inert gasses work by removing the oxygen in the hazard to a point where it will not support a fire, but still high enough to support life. Design considerations when using inert gasses are pressure venting and volume. It is critical to design the system to achieve the correct concentration, and not remove too much oxygen in the room. Plus, venting of inert gasses is important as it displaces the air volume in the hazard area. AFT can assist in determining which agent is best suited to protect the hazard area (includes detection and control for the system).

• curtain board

a partition of noncombustible material fitting tightly against a ceiling and intended to prevent or retard the spread of fire and heat.

• water curtain

a sheet of water from a series of sprinklers for protecting the walls and roof of a building from fires outside the building.

• sprinkler head

fusible metal link glass bulb early suppression fast-response sprinkler (ESFR) quick-response, early suppression sprinkler (QRES) extended coverage sprinkler

• smoke exhaust shaft

is typically protected via passive fire protection means, subject to fire testing (typically to ISO6944) and listing and approval use and compliance. It is used to remove smoke from buildings, ships or offshore structures to enable emergency evacuation as well as improved firefighting.

• manual station

the manual station is operated by hand. Manual stations serve to spread the alarm that has already been detected by other means, either human or automatic.

• standpipe and hose system (Class I, Class II, Class III)

● Class I. Intended for fire department use only. This type of system is equipped with a 2 1 ⁄2 in. (65 mm) angle valve for hose attachment. The system is not provided with hose; the fire department will use their own hose (see Exhibit 3.1). ● Class II. Previously intended for building occupant use only. NFPA 14, Standard for the Installation of Standpipe and Hose Systems, now restricts this type of system for use by trained industrial fire brigades. The Class II system is usually equipped with 1 1⁄2 in. (65 mm) hose in varying lengths of 50 to 150 ft (50 m to 45.7 m) and is designed to discharge water at a rate of 50 gpm (189 L/m) per hose rack at a pressure of 65 psi (4.5 bar). ● Class III. A combination of Class I and Class II. This type of system is usually equipped with a 2 1⁄2 in. (65 mm) angle valve for fire department use and a 1 1⁄2 in. (40 mm) hose rack assembly for industrial fire brigade use, although a 2 1⁄2 in. (65 mm) hose valve with a 2 1⁄2 in. 1 1⁄2 in. (40 mm) reducer and a 1 1⁄2 in. (40 mm) cap and chain can, by definition in NFPA 14, be used to satisfy the Class III standpipe system requirement. It is important to note that many building codes will require the installation of a Class III standpipe system. Such a requirement can be met without the installation of a hose rack assembly (see Exhibit 3.2).


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