fire alarm system notification appliances
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Fire Alarm System Notification Appliances
Chapter 13
Page 394
2
Objectives
• Discuss the four groups of notification signals, explain why the temporal-coded signal is now the national standard signal, and outline research conducted with respect to recognition of the temporal-coded signal
• List the available types of audible notification appliances
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Objectives
• Evaluate public- and private-mode audibility requirements for fire alarm systems and explain why the two modes differ
• Determine the effectiveness of an audible notification appliance, given ambient sound levels, door or wall attenuation, and inverse square law losses
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Objectives • Compare wall-mounted and ceiling-
mounted visible notification appliance requirements
• Locate visible notification appliances in a room, corridor, or sleeping room
• Use the multiple-square layout to optimize visual notification appliance location
• Explain the function of an annunciator panel
5
Objectives • Determine the reasons why tactile
notification appliances may be necessary, and discuss how they can be used effectively
• Compare NFPA 72, ANSI, UL, and ADA requirements for visible notification appliances
• Discuss the conditions that make strobe synchronization necessary
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Audible Notification Appliances
• Audible Notification Appliance Audibility Requirements
• Public-Mode Audibility Requirements (see Tables 13-1 and 13-2, Pages 399-400)
• Private-Mode Audibility Requirements• Audible Notification Appliance Intelligibility
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Audible Notification Appliances
• Audible Notification Appliance Location (see Tables 13-3 and 13-4 Page 401)
• Inverse square law: as the distance from the ear to the notification appliance doubles, sound is reduced by 6 dB along the centerline of the notification appliance
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Audible Notification Appliances
Figure 13-5. Illustration of the inverse square law; sound pressure reduces 6 dB every time the distance from the audible notification appliance doubles
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Audible Notification Appliances
Figure 13-6. Off-centerline sound losses; persons “B” and “C” are at the same lineal distance from the notification appliance as person “A”
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Ex. 13-6: Calculation of Audible Notification Appliance Audibility
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“Exit Marking” Audible Notification Appliances
• “Exit marking” audible notification appliances: installed at the entrance of all building exits and areas of refuge– Emit distinct sound pressure levels capable of
directing occupants to the exits
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Visible Notification Appliances
• Candela (cd): the standard unit of light intensity measurement
• Blackbody: ideal body that would absorb all incident radiation and reflect none
• Public-Mode Visibility Requirements• ADAAG Visible Appliance Requirements• Private-Mode Visibility Requirements
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Visible Notification Appliances
• Wall-Mounted Visible Notification Appliance Location
• Ceiling-Mounted Visible Notification Appliance Location (see Table 13-5, Page 410)
• Visible Appliance Spacing in Rooms That Are Not Square
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Visible Notification Appliances
• Multiple Square Layout of Visible Notification AppliancesOptimization of Visual Notification Coverage
• Placement of Visible Appliances in Corridors (see Table 13-6, Page 415)
• Spacing of Visible Appliances in Sleeping Areas (see Table 13-7, Page 417)
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Visible Notification Appliances
Figure 13-12. Optimization of visible notification coverage (part 1)
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Visible Notification Appliances
Figure 13-12. Optimization of visible notification coverage (part 2)
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Visible Notification Appliances
Figure 13-13. Corridor spacing of visible appliances
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Visible Notification Appliances
• Combination Audible/Visible Notification Appliances
• Combination audible/visible notification appliance: has both audible and visible notification components
• Synchronization of Visible Appliances
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Textual Audible and Visible Notification Appliances
• Textual visible notification appliance provides alphanumeric fire alarm notification or instructions
• Usually on an annunciator, fire alarm control unit, or a panel remote from the main FACU
• Textual notification information can be provided by LEDs on a display window
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Textual Audible and Visible Notification Appliances
• Can provide more precise information than by other audible and visible appliances
• Can provide notification for persons with hearing disabilities
• Central station operators, security guards, and fire watch personnel often are provided with textual appliances
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Annunciation Notification Appliances
• Annunciator panel: provides visible notification of the location of an initiating device by zone and floor
• Annunciator should be placed in a fire control room or at main building entrance– Fire service personnel can identify fire location
and implement suppression strategy
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Tactile Notification Appliances
• Audible appliances are effective for those who can hear
• Visible appliances are effective for those who can see
• Combination audible/visible appliances are effective for those with either sense
• Tactile notification appliances are for individuals who can neither see nor hear
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Tactile Notification Appliances
• With tactile notification appliances, training must be provided so that occupants can find exit building on their own
• If this is not possible, a method must be provided for the notification of supervisory personnel who are responsible for assisting occupants to safety
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Tactile Notification Appliances
• Bed shakers are an alternative for rousing sleeping individuals
• Some tactile appliances, such as vibrating belt pagers, and variable-speed ceiling fans, cannot be readily supervised, and are therefore considered supplemental notification appliances
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Summary
• Notification appliances must be selected carefully to be congruent with the needs of – Building occupants– Supervisory personnel– Security personnel who interpret the alarm– Fire service responders
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Summary
• Notification appliances must– Accommodate persons with disabilities – Arouse a sleeping person – Spur a person who is awake to leave the
building or relocate to a fire-safe area
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