by billy nigzus term 1 10-10-14 fire alarms. what are fire alarms ? fire alarms are a device or a...
TRANSCRIPT
BY BILLY NIGZUS
TERM 1 10-10-14
FIRE ALARMS
WHAT ARE FIRE ALARMS ?Fire alarms are a device or a system that alert people when there is a fire.
• A device could be a battery operated smoke detector.• A system is a group of devices such as pull stations, smoke detectors, and a system
panel.
How do you activate the system you ask? There are 2 types of devices that make the alarm sound, there is a pull station, and a smoke detector.
• A pull station is a device on the wall you pull when there is a fire.• A smoke detector is a device on the ceiling that when it senses smoke it activates
the alarm.
HOW DOES THE FIRE DEPARTMENT KNOW ABOUT THE ALARM GOING OFF ?
When you set off the alarm several things happen:
• When you pull the pull station it throws a switch which completes a circuit.
• A signal goes to the panel and sets off the zone where the pull station is.
• Two things happen
• the alarms go off in the building
• there is a phone line from the panel to the fire alarm company
• the alarm company’s 24 hour fire alarm tracker then calls dispatch and
they set a tone out to the fire department that there is a fire call.
TYPES OF SMOKE DETECTORS
If there is a fire and no one is around to pull the alarm, what
happens?
• A smoke detector acts the same as a pull station when it detects smoke.
• There are two types of smoke detectors
• Ionization: better at detecting fast fires
• Photoelectric: better at detecting smoldering fires
A VIDEO ON PHOTOELECTRIC VS IONIZATION SMOKE DETECTORS
HTTPS://WWW.YOUTUBE.COM/WATCH?V=ZROLXH8GUCU
• 6:34
OTHER TYPES OF DETECTORS
Heat detectors
• They sense a rise in temperature usually above 125oF
• Usually used where people are not there for 24 hours
• Places such as garage, basement, or attic
CO detectors
• They sense carbon monoxide
• It is a odorless, tasteless, colorless gas that will kill you.
• Produced by burning fuel (Wood, Oil, and Propane, etc.)
• Two common types of CO detectors
• Combination with smoke detector (does both at the same time)
• Plug in CO detectors (CO only but easy to install)
EXPERIMENT What will we learn?
• How fire alarms work?
• How do they activate
• Manually by pull station
• Automatically by smoke detector
• What happens?
• The alarm will go off inside the building
• The alarm panel calls dispatch
SOURCES
YOUTUBEHTTPS://WWW.YOUTUBE.COM/WATCH?V=ZROLXH8GUCU
GOOGLE IMAGES
NFPA, NATIONAL FIRE PROTECTION ASSOCIATION