Module 5. Fire and Emergency Alarm System Part I- Basics

Transcription

1 Module 5 Fire and Emergency Alarm System Part I- Basics 1

2 This module will describe: 1. Components and the arrangements of components in fire and emergency alarm systems. 2. How these systems work. 3. The NFPA standards that govern these components and systems. 2

3 Power Supply A source of electrical operating power, including the circuits and terminations connecting it to the dependent system components. In alarm systems there much be two supplies of power (primary and secondary) NFPA Standards 72: National Fire Alarm and Signaling Code 70: National Electrical Code 3

4 Control Unit A system component that monitors inputs and controls outputs through various types of circuits. NFPA Standards 72: National Fire Alarm and Signaling Code 4

5 Alarm Initiating Devices A system component that originates transmission of a changeof-state condition, such as in a smoke detector, manual fire alarm box, or supervisory switch. Can be manual or automatic NFPA Standards 72: National Fire Alarm and Signaling Code 5

6 Alarm Initiating Devices: Manual Pull Stations Manual Red in color Located about 4 feet above the floor and close to exits 6

7 Alarm Initiating Devices: Smoke Detectors Automatic A listed device that senses visible or invisible particles of combustion Two main types ionization photoelectric Wikimedia Commons 7

8 Alarm Initiating Devices: Heat Detectors Automatic Initiates an alarm when the thermal energy of a fire increases the temperature of a heat sensitive element. Two main types Rate-of-rise Fixed temperature Wikimedia Commons 8

9 Alarm Initiating Devices: Radiant Energy Detectors Automatic Responds to the radiant energy that has traveled from the fire to the detector Two main types Flame detector Smoke or ember detector Desu Systems 9

10 Alarm Initiating Devices: Gas Detectors Automatic Detects the presence of various gases Two main types Fixed Portable Sensidyne 10

11 Alarm Initiating Devices: Combination Detectors A device that: responds to more than one of the fire phenomena; or employs more than one operating principle to sense one of these phenomena. Examples: Heat detector with a smoke detector Rate-of-rise and fixed-temperature heat detector 11

12 Alarm Initiating Devices: Sprinkler Water Flow Switches Automatic Initiates an alarm signal when the flow of water through the wet pipe sprinkler system is greater than that going through one sprinkler head Home Security Store 12

13 Alarm Notification Appliances A fire alarm system component such as a bell, horn, speaker, light or text display that provides audible, tactile or visible outputs, or any combination thereof. A Mircom horn/strobe fire alarm notification appliance The primary purpose is to convey information to building occupants during a fire emergency NFPA Standards 72: National Fire Alarm and Signaling Code 13

14 Alarm Notification Appliances: Audible Horns & Speakers Must be audible and intelligible Fire Alarm-Security 14

15 Alarm Notification Appliances: Visible Strobe lights or illumination Must be accessible and visible Fire Alarm-Security 15

16 Supervision A visual and audible alarm signal given at the central safety station to indicate when the system is in operation or when a condition that would impair the satisfactory operation of the system exists. NFPA 13: Standard for the Installation of Sprinkler Systems 72: National Fire Alarm and Signaling Code 16

17 Supervision: Protected Premises Protected premises are all buildings, structures, facilities, real property, or portions thereof protected by an alarm system. A protected premises alarm system is designed to: Warn building occupants to evacuate the premise Actuate the building s fire-protection features Provide environmental protection 17

18 Supervision: Supervising Station A facility that receives signals and at which personnel are in attendance at all times to respond to these signals Three types Remote supervising-station fire alarm systems Propriety supervising-station systems Central-station fire alarm systems 18

19 Supervision: Remote Station A supervising station: to which alarm, supervisory, or trouble signals or any combination of those signals emanating from protected premises fire alarm systems are received where personnel are in attendance at all times to respond. must have a minimum of two operators on duty at all times to monitor signals 19

20 Supervision: Propriety Supervising Station A supervising station: under the same ownership as the protected premises fire alarm system(s) that it supervises to which alarm, supervisory, or trouble signals are received where personnel are in attendance at all times to supervise operation and investigate signals. May supervise one or more properties. 20

21 Supervision: Central Station A supervising station: that is listed for central station service that commonly provides less stringent supervising station services such as remote supervising station services. It is where the monitoring of the system and signals occurs retransmission of signals to the appropriate emergency-response service and record keeping will occur Wikimedia Commons 21

22 Supervision: Digital Alarm Communicator Transmitter Transmit an alarm signal from the property to the central supervising station. Is connected to the public-switched telephone network upstream of any telephone system on the property. Digital alarm communicator systems are the most widely used means is a digital alarm communicator system. 22

23 Single-Station Smoke Alarms A detector comprising an assembly that incorporates a sensor, control components, and an alarm notification appliance in one unit operated from a power source either located in the unit or obtained at the point of installation. NFPA Standards 72: National Fire Alarm and Signaling Code Wikimedia Commons 23

24 Multiple-Station Smoke Alarms Two or more single station alarm devices that can be interconnected so that actuation of one causes all integral or separate audible alarms to operate; or one single station alarm device having connections to other detectors or to a manual fire alarm box. NFPA Standards 72: National Fire Alarm and Signaling Code 24

25 Zoned Fire Alarm Systems A system where the entire facility is subdivide into into zones all initiating devices in any one particular zone are indicated as that zone on the control panel Often referred to as a conventional system NFPA Standards 72: National Fire Alarm and Signaling Code 25

26 Addressable Fire Alarm Systems A system or a part of a system where one can pinpoint which device has been activated. Each initiating device is assigned a number or address NFPA Standards 72: National Fire Alarm and Signaling Code 26

27 Wireless Fire Alarm Systems A system or a part of a system that can transmit and receive signals without the aid of wire. Two basic forms of commercial wireless systems: True Wireless Only wireless from the initiating point to a receiver NFPA Standards 72: National Fire Alarm and Signaling Code 27

28 Lessons Learned from Module 5 Fire alarm systems require two power supplies. There are many different initiating devices, both manual and automatic, such as pull boxes and heat detectors. A supervising facility is a facility that receives signals and at which personnel are in attendance. Fire alarm systems transmit information back in different ways, such as zoned where all initiating devices in any one particular zone are indicated as that zone on the control panel. 28